Northern Territory Department of Primary Industry, Fisheries and Mines
Primary Industries Technical Annual Report 2004-05
Primary Industries Berrimah Farm Makagon Road Berrimah NT 0828 GPO Box 3000 Darwin NT 0801 AUSTRALIA www.primaryindustry.nt.gov.au [email protected]
Tel: +61 8 8999 2202 Fax: +61 8 8999 2307
Technical Bulletin No. 323 Price: $11.00 ISSN: 0158-2763
Please note:
Although the research, development and extension work outlined in this Technical Annual Report was conducted under the previous Department of Business, Industry and Resource Development, it is being reported under the new Department of Primary Industry, Fisheries and Mines (DPIFM). This is being done in order to promote the new DPIFM among the Northern Territory primary industries and because the work is of an ongoing nature.
DISCLAIMER
While all care has been taken to ensure that information contained in this Technical Bulletin is true and correct at the time of publication, changes in circumstances after the time of publication may impact on the accuracy of its information.
The Northern Territory of Australia gives no warranty or assurance, and makes no representation as to the accuracy of any information or advice contained in this Technical Bulletin, or that it is suitable for your intended use.
You should not rely upon information in this publication for the purpose of making any serious, business or investment decisions without obtaining independent and/or professional advice in relation to your particular situation.
The Northern Territory of Australia disclaims any liability or responsibility or duty of care towards any person for loss or damage caused by any use of or reliance on the information contained in this publication.
October 2005
CONTENTS
INTRODUCTION ...... 5
PASTORAL...... 7
SERVICE: AGRICULTURE ...... 7
Program: Cattle Production from Mixed Farms ...... 7 Sub-program: Livestock Management ...... 7 Program: Improved Pasture, Hay and Seed Production ...... 26 Sub-program: Pasture Development...... 26 Program: Irrigation Production...... 32 Sub-program: Douglas Daly - Irrigated Crops...... 32 Sub-program: Cotton...... 44 Program: Dry Land Cropping...... 48 Sub-program: Farming Systems ...... 48 Program: Buffalo Production...... 49 Program: Agroforestry...... 53 Program: Extension ...... 61 Program: Weeds ...... 62
SERVICE: PASTORAL PRODUCTION...... 71
Program: Native Pasture Management ...... 71 Program: Grazing Management...... 75 Program: Herd Management ...... 85 Program: Extension and Training ...... 93 Sub-program: Indigenous Pastoral Program ...... 100
SERVICE: ANIMAL DISEASE CONTROL ...... 102
Program: Berrimah Veterinary Laboratories ...... 112 Sub-program: Diagnostic Pathology ...... 114 Sub-program: Virology ...... 117
SERVICE: LIVESTOCK MARKET ACCESS ...... 125
Program: Livestock Market Access...... 125
SERVICE: RESEARCH FARMS...... 140
Program: Research Farms...... 140
SERVICE: TECHNICAL SERVICES - LIVESTOCK EXPORTS...... 143
Program: Technical Services...... 143 Sub-program: Livestock Exports...... 143
SERVICE: WATER MICROBIOLOGY...... 148
Program: Water Microbiology ...... 148 Sub-program: Water Microbiology Laboratories ...... 148
RESOURCE PROTECTION...... 150
SERVICE: PLANT HEALTH (PRODUCTION)...... 150
Program: Plant Health (Production) ...... 150
SERVICE: PLANT HEALTH (PROTECTION)...... 188
Program: Plant Health (Protection) ...... 188
HORTICULTURE...... 208
SERVICE: HORTICULTURE INDUSTRY INFORMATION SERVICE ...... 208
Program: Horticulture Industry Development Service...... 208 Program: Indigenous Horticulture Development ...... 220 Program: New and Improved Products...... 222 Program: Production Systems ...... 241 Program: Supply Chain Development...... 269 Program: Horticulture Information Service...... 272
PUBLICATIONS, CONFERENCE PAPERS AND PRESENTATIONS ...... 274
Technical Annual Report 2004-05
INTRODUCTION
Following the Northern Territory elections in 2005, Government Departments were restructured in order to improve the efficiency of delivery of services to the community. To focus more on the provision of services to the three natural resource base industries in the Territory, the Department of Business, Industry and Resource Development became the Department of Primary Industry, Fisheries and Mines (DPIFM).
This Technical Annual Report presents a summary of research, development and extension services provided to the Territory’s primary industry in 2004-05 by Primary Industries in DPIFM. Those services covered the three major areas of primary industry: pastoral, resource protection and horticulture. Many services are provided through investigative projects which are conducted either on government research farms or on private farms. The aim is to deliver timely solutions to problems that limit the profitability and sustainability of primary industry enterprises.
The Pastoral Division provides research, development and extension services to the pastoral and agricultural industries to improve productivity, profitability and sustainability. It also provides the livestock industries with market health assurance services that enable them to operate in interstate and overseas markets.
The pastoral industry comprises some 216 pastoral leases, plus freehold mixed farms and Aboriginal cattle properties. Together they manage more than half the land mass of the Territory.
In 2003-04, about 538 600 head of cattle were turned off from Territory pastoral properties, which was 32% higher than in 2002-03. Out of that number, 43% or 233 930 animals went to the live export market, 56% or 299 365 went inter-state and only 1% or around 5300 were slaughtered in the Territory.
It is estimated that there were about 1.9 million head of cattle in the Territory in 2003-04, which is an all time high, representing about 7% of the total Australian cattle population.
There was a 10% decline in the number of live cattle exported to South East Asia and the Middle East in 2003-04. This was due to a combination of factors including a higher value of the Australian dollar, higher prices for cattle in the Australian market and some competition in Asia from lower priced buffalo meat.
Indonesia was once again the largest market for live cattle from the Territory, accounting for 69% of all live cattle exports. However, the total number of cattle exported to Indonesia declined by 7%, to 160 373. This was largely due to a backlog of cattle in the Indonesian market.
The agricultural industry continues to be based on mixed farming, including cattle production on improved pastures, hay and seed production, and irrigated crop production.
The value of field crops produced in 2003-04 is estimated at $11.3 million, which is similar to that in 2002-03.
At present, mixed farming operations in the Katherine, Douglas/Daly and Darwin areas focus mainly on servicing the live cattle export industry. As a result, hay and fodder crops dominate production, which increased by 9% in 2003-04 over the previous year.
Farm forestry is becoming a potential alternative for land development and rural business diversification for NT primary producers. A strategy for African mahogany hard wood timber production in the Top End was developed and launched in 2004. A multi-million dollar private forestry enterprise is developing on Melville Island. It exported 14 000 tonnes of logs on a trial basis in 2004.
The Resource Protection Division ensures that pests, diseases and chemical residues do not restrict the production and market access of livestock, plants and plant products. It informs, advises and facilitates
5 Primary Industries services for clients in the regulatory control of animals and plants, and in general agricultural resource protection, including plant health, incursion management and pesticide registration and regulation.
The Entomology, Plant Pathology and Interstate Quarantine Sections provide services in plant health for production and for protection. A successful program to eradicate grapevine leaf rust in the Darwin area was initiated in 2003. It is progressing well and is expected to achieve its objective in 2006. Surveillance and public awareness were maintained for the red imported fire ant, which is a major pest in the greater Brisbane area where it is currently being eradicated. Other programs conduct surveillance for exotic fruit flies, plant pests and diseases that may have entered the Territory during the extensive movement of personnel and equipment during the East Timor crisis. During the year, experienced staff provided assistance to a range of Australian organisations involved in plant health and quarantine work overseas.
The Agricultural and Veterinary Chemicals Control of Use Act became law in May 2005. Considerable progress was made on developing new plant health legislation. The process to obtain accreditation to the National Association of Testing Authorities continued for the Chemistry laboratory. A similar process for accreditation will commence for the Entomology and Plant Pathology diagnostic laboratories.
The estimated gross value of production for the horticulture industry in 2004 was $98.6 million from an estimated 7000 hectares of land, which is an increase of 11.9% over the previous year. With a production of 19 611 tonnes in 2004 valued at $42.9 million, mangoes continued to dominate the industry. There are approximately 800 000 mango trees in the Territory with a potential to produce up to 8 million trays in the next five years. There are increasing plantings of new commercial varieties including Calypso and Honey Gold and of green mangoes such as Keow Savoy, Falan and Nam Dok Mai.
Banana production in 2004 reached 2898 tonnes valued at $4.7 million. Production continued to decline due to Panama disease. Research is continuing to identify resistant varieties and to develop appropriate management procedures to reduce the spread of the disease.
Table grapes are the main horticultural crop in Central Australia. Production from about 250 hectares was 1508 tonnes in 2004, valued at $8.3 million. Root-knot nematode has been identified as the major cause of a decline in the industry. As growers replace own-rooted vines with grafted vines on nematode-resistant rootstocks, production will probably remain low over the next few years as the industry rebuilds.
Total vegetable production reached 5967 tonnes valued at $14.5 million. More than 50 farms now supply Asian and traditional vegetables to southern and local markets.
Melon production increased to 7688 tonnes in 2004 from the Katherine, Douglas Daly and Darwin areas to become a major crop in the NT, valued at $6.4 million.
The nursery industry was valued at $13 million in 2004. Cut-flowers were valued at $4 million, consisting mainly of heliconia and ginger, which have rapidly increased in production.
Rambutans were again exported to Japan and southern markets. In 2004, 108 tonnes were produced, valued at $0.9 million.
The Fisheries Group of DPIFM will be reporting its research, development and extension activities separately in Fishery Status Reports 2004, which will be available soon from the Publications Section at Berrimah Farm. Similarly, the Mines Group will provide a separate annual report which can be obtained from that Group.
Feedback and suggestions for improvement of future editions of this Technical Annual Report are most welcome. Please send your suggestions to the Technical Publications Editor, Primary Industries, DPIFM GPO Box 3000 Darwin NT 0801, or call (08) 8999 2202.
6 Technical Annual Report 2004-05
PASTORAL SERVICE: AGRICULTURE
Program: Cattle Production from Mixed Farms
Sub-program: Livestock Management
PROJECT: Douglas Daly Research Farm Weather Recording
Project Officers: P. Shotton, T. McComish, and Bureau of Meteorology
Location: Douglas Daly Research Farm (DDRF)
Objective:
To observe, monitor and record daily weather information from the DDRF manual and automatic weather stations.
Background:
Weather plays a vital role in farm productivity. Weather observations are a vital component of any research carried out on the research station.
Method:
Manual meteorological observations include evaporation, wind run, minimum and maximum water temperatures, and rainfall.
The automatic weather station records wind run; wind speed, gusts and direction; wet and dry bulb temperatures for humidity and dew point; minimum and maximum temperatures; rainfall amount and intensity; and barometric pressure.
Results:
All past DDRF weather information has been recorded and is available on request. Daily weather data is also sent to the Bureau of Meteorology. Table 1 shows monthly weather data for the Douglas River, compiled by the Bureau of Meteorology Darwin.
7 Pastoral
Table 1. Douglas River weather data
Element Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Mean daily maximum temp (ºC) 33.9 32.7 33.9 34.9 33.1 31.5 31.7 33.6 36.5 37 36.9 34.9 Highest daily maximum temp (ºC) 39.2 37.1 37.6 38.5 38.4 36.6 36.6 38.7 40.6 42.6 41.5 40.7 Mean daily minimum temp (ºC) 23.9 23.9 22.9 20.8 16.9 13.9 13 15.1 19.1 22.4 23.4 23.8 Lowest daily min temp (ºC) 19.5 19.5 11.6 10 5.5 4 2 2.5 4.5 11.5 14.2 16.4 Mean 9 am air temp (ºC) 27.6 26.9 27.2 26.8 24.1 21.4 20.7 23 26.9 28.8 29.2 28.5 Mean 9 am relative humidity (%) 83 87 83 73 61 56 57 59 64 67 71 78 Mean 3 pm relative humidity (%) 62 68 56 41 34 29 29 26 25 34 41 56 Mean monthly rainfall (mm) 275.4 292.8 226.1 41.5 8.4 3 3.4 0.8 4.6 38.7 114.7 198.7 Mean no. of rain days 17.7 18.4 15.1 4.7 1.2 0.2 0.3 0.2 0.9 4.2 9.9 13.7 Highest monthly rainfall (mm) 786.6 572 636.4 229 96.8 86.8 47.7 8.4 37.6 124.8 241.6 515.6 Lowest monthly rainfall (mm) 106.3 77.4 63.4 0 0 0 0 0 0 0 30.4 30 Highest recorded daily rainfall (mm) 194.6 206.4 155 73 52.8 40.1 41.8 8.4 37.2 93.5 98 113 Highest recorded wind gust (km/h) 59.4 59.4 64.8 51.8 53.6 51.8 50 50 50 48.2 66.6 70.2 Mean daily evaporation (mm) 5.6 5.2 5.3 6 6.4 6.2 6.4 7.2 7.7 7.6 6.8 6.1
Details for 2004 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Mean daily max temp (ºC) 33.3 31.7 33.6 35 32.8 30.5 30.1 33.3 33.7 39.2 36.7 37.1 Highest temperature (ºC) 35.4 35.4 35.5 36.3 35.6 34.4 33.8 35.2 37.9 41.8 39.2 40.5 Mean daily min temp (ºC) 24.4 24 24.2 20.2 19.7 13 11.8 14 20.8 22.7 24 24.4 Lowest temperature (ºC) 22.3 21.2 20.2 16.9 12.4 5 5.2 7.1 11 18.4 21.4 22.4 Mean daily pan evaporation (mm) 4.7 3.7 4.8 6.6 6.6 5.7 5.9 7.2 8.5 7.5 6 6.2 Monthly rainfall (mm) 237.8 494.4 157.6 21.4 31.8 0.8 0 0 0 4.4 102.6 127.6 Rain days 21 26 23 3 4 1 0 0 0 1 9 14
PROJECT: Pasture Species Evaluation under Grazing at DDRF - Buffel/Legumes
Project Officers: P. Shotton, B. Lemcke and L. Huth
Location: Paddock 50, Douglas Daly Research Farm (DDRF)
Objective:
To monitor the value of a companion legume with buffel grass in terms of nitrogen availability, pasture quality, quantity and the persistence of the legume species.
Background:
Buffel grass (Cenchrus ciliaris) is a commonly used improved pasture in the Top End, south of and including the Douglas-Daly region. As established buffel grass pasture tends to grow in clumps, a favorable legume companion species would be beneficial to help utilise the area between buffel plants and ideally provide nitrogen to the grass, resulting in higher quality and better yielding pastures. Higher protein content in the diet, due to the legume, would be an added bonus.
The project follows a non-grazed plot trial in 1996-98 that evaluated the benefits of six tropical pasture legume species as companions to buffel grass (seeTechnote 110).
8 Technical Annual Report 2004-05
Method:
On 6 January 2000, seed of five pasture legume species was planted in a 4 ha paddock (paddock 50) at DDRF. The legumes used were Wynn cassia (Chamaechrista rotundifolia), Verano stylo (Stylosanthes hamata), Oolloo (Centrosema brasilianum), Maldonado (Macroptilium gracile) and Milgara blue pea (Clitoria ternatea). The legume treatments and control - buffel only - were replicated four times and randomised with a plot size of 12 m x 130 m.
In December each year approximately 50 kg/ha of Goldphos 20 or equivalent fertiliser was applied to the area.
No grazing was allowed in the first wet season to allow legumes to set seed. The paddock is stocked with five Brahman weaner steers at 1.25 head per hectare for a 12 month period. Steers are changed over in late June each year. Cattle weights, condition, and fat scores are recorded monthly.
In 2004 – 05, a mix of steers was used: Brahman, Composites and Droughtmaster.
The animals are supplemented with Uramol blocks in the dry season and Phosrite blocks in the wet season. Intake is recorded monthly. Consumption was similar in all seasons. Average intake was 106 g/head/day Uramol during the dry season and 68 g/head/day Phosrite during the dry season.
Broadleaf weeds were controlled with Starane as a post-planting/pre-emergent herbicide in January 2000. Some hand-weeding and spot-spraying is carried out each wet season for broad-leaf weeds, mainly spiny head sida (Sida acuta) flannel weed (Sida cordifolia), Hyptis (Hyptis suaveolens) and senna (Cassia obtusifolia).
Pasture composition and yield were assessed twice each year in December and May using Botanal. Soil and plant samples are taken from each plot to compare the differences in soil and plant nutrients. The pasture from cut quadrats also indicates actual yields to construct regression equations for Botanal determinations.
Results:
During the first two seasons, all legumes established well. The most prolific were Milgara blue pea, Oolloo and Maldonado. Wynn cassia and Verano stylo were less prolific than the twining legumes. Verano, Wynn and blue pea seeded well but Oolloo and Maldonado seeded poorly. However, all legumes seeded well in the second year. Results from the April 2001 biomass harvest indicated that the greater the legume content, the higher was the overall yield, although grass yields in the Oolloo treatments were lower, indicating Oolloo was competing with buffel grass.
During the first three years, the proportion of legumes declined, with only Oolloo sustaining a grass/legume mix (see Figure 1). Very few legumes were present during the 2003-04 wet season; however in the following wet season, the Oolloo, Verano and Wynn groups increased in the proportion of legume, particularly Wynn and Oolloo.
9 Pastoral
70 60 50 2001 2002 40
% 2003 30 2004 20 2005 10 0 Mald Milgara Oolloo Verano Wynn
Figure 1. Species proportional yields of paddock 50 buffel/legume trial
Plant analysis results suggest that the higher the proportion of legume content, the higher is the nitrogen in the companion buffel grass. This could be visibly seen throughout the wet season and early dry when the Oolloo treatments had a darker green colour, with the buffel grass flowering earlier and having a denser stand of pasture.
The average 12-month live-weight gain was lower compared with past years (see Table 1) and was slightly below the average live-weight gain of the other species paddocks. This may have been because of the different mix of steers used, the shorter rainy season or the decline of legume present in the pasture.
Table 1. Mean cattle annual live-weight gains
Year 2001-02 2002-03 2003-04 2004-05 Paddock 50 average wt. gain 208 kg 176 kg 190 kg 168 kg
Conclusion:
Pasture mix is affected in the long-term by hard seediness, climatic conditions, insect pests and palatability of the legumes. Different management of the pasture such as non-grazing to allow seed set every second or third year will improve the sustainability of the pasture legume. A limitation of the trial was that the animals could selectively graze plants of preference, which could result in over-grazing, and depletion of some legumes, allowing the less palatable species to survive. The promising performance of Oolloo as a companion legume in buffel grass has resulted in further monitoring in paddock 535, where the legume was introduced in December 2002.
10 Technical Annual Report 2004-05
PROJECT: Grain Sorghum Varieties for the Douglas Daly Region
Project Officer: P. Shotton
Location: Douglas Daly Research Farm (DDRF)
Objective:
To grow and trial new and commercially available grain sorghum varieties at DDRF to determine those suitable for the Douglas - Daly District.
Background:
Over the past ten years replicated sorghum variety trials were conducted at DDRF. During the past six years sorghum seed supplied by the Pioneer and Pacific seed companies has been used. Among the varieties evaluated are those which have shown promise in past years and new varieties, which may suit the Top End climate. Trial results will provide yield and suitability information on commercially available varieties.
Method:
Trial location: Paddock 9, DDRF. Trial area: 1.2 ha Varieties: Seven by four replications. Plot size: 50 x 8 rows. Weed control: Glyphosate @ 2.5 L/ha. Atrazine 500 @ 2 L/ha. Fertilisers: 150 kg/ha NPKS (16-17-0-12) 80 kg/ha urea 100 kg/ha muriate of potash
The trial area was planted (zero-till) within a bulk area of grain sorghum on 20 December using an 8-row zero-till planter. Row spacing was at 75 cm with a planting population of approximately 200 000 seeds per hectare.
Pre-emergent herbicide (Atrazine 500) was applied for the control of various grasses and broad leaf plants.
Each plot was monitored and evaluated for plant population, flowering and maturing dates, insect and pest occurrence, plant height, head type, resistance to head mould and leaf disease, plant lodging and hand harvest yields,
Results:
Rainfall was slightly below average, reaching 980 mm for the season. Crop emergence was patchy due to uneven mulch cover and some problems with planter seed displacement and bird damage.
Maturing dates were later than usual this season for all varieties and unevenness of maturity was also noticed. This was probably due to the heavy January rainfall and uneven distribution of fertiliser.
Most varieties had reasonable characteristic grades for leaf disease, head mould, head exertion and height. The highest yielding varieties were Graze n Sile, Pacer, Bonus and MR43 (see Table 1).
11 Pastoral
Table 1. Average results of four replications
Variety Grain First 50% Head Height Leaf Head Head Plant (kg/ha) flower flower type (m) disease mould exertion pop. Graze N Sile 4427 68 72 C 2.0 4 4 4 99 000 Pacer 4187 66 69 O 1.2 3 3 3 102 300 Bonus 4005 71 74 C 1.3 3 3 4 88 000 MR 43 3577 64 69 O 1.2 2 3 3 102 300 Maxi 3360 66 69 SC 1.3 3 3 4 91 700 8118 3327 69.0 73 SC 1.4 3 3 4 91 000 Buster 2980 66 69 SC 1.1 3 3 3 88 000
Head type Head Exertion Leaf disease Flowering: Days after planting O = Open 1 = Poor exertion 1 = Severe leaf disease SO = Semi open 5 = Good exertion 5 = No leaf disease SC = Semi closed C = Closed
500 400 300 200 100 Rainfall in mm Rainfall 0 Nov. Dec. Jan. Feb. Mar. Apr. Month
Figure 1. DDRF rainfall in 2004-05
PROJECT: Sucker Regrowth Control in Improved Pastures
Project Officers: P. Shotton and C. Hazel
Location: Douglas Daly Region
Objective:
To trial, monitor and record the short and long term effectiveness of sucker regrowth control methods in improved pastures using herbicide pellets and wipers.
Background:
Mechanical clearing of native growth for improved pasture production often leads to sucker re-growth from root stocks and seed banks. Other woody and grass weed invasion generally occurs after clearing and ground disturbance. The presence of these unwanted species reduces pasture production and creates problems in pasture maintenance and management.
12 Technical Annual Report 2004-05
The control of woody weeds in pastures is an ongoing concern, particularly where selective herbicides are not available or are uneconomic. In mixed pasture, herbicide control methods are more difficult because there are few selective herbicides available -to our knowledge- or they are expensive.
A number of methods are available to control re-growth, including ecological, mechanical and chemical. However not all are suitable for established pastures.
Herbicide wipers are one method to manage tall weeds and sucker re-growth in crops, pastures and forestry. Success depends on location, weed species, application methods and chemicals used. The benefit of herbicide wipers is that the chemical is applied only to the target weed, thereby reducing waste, using cheaper non-selective herbicides and eliminating spray drift.
A number of replicated and non-replicated trials were conducted in the Top End using herbicide wipers with many different chemicals and adjuvants. The major contributing factor for effectiveness has been the height and density of the weed mass and the speed of application. Generally, the taller and leafier the weeds, the greater is the chemical contact and better is the control. Slower application results in better herbicide contact.
The most universal chemical mix is Glyphosate with 1% adjuvant of LI 700 and a non-ionic 100% wetter. The solution of one part chemical (Glyphosate 450) to 10 parts water controlled most actively growing broad-leaf and grass weeds in mixed pastures and legume hay crops. The most effective chemical for sucker re-growth when using a wiping method of application is Grazon DS.
Application of Graslan pellets is an alternative way of controlling various woody weeds in pastures. Graslan pellets work through application to the soil surface and sufficient rainfall is needed to incorporate the chemical into the root zone, which is then taken up by the woody weeds. Graslan pellets have been extensively used in other States. However, there is less information on its use in the NT.
Method:
A non-replicated trial was conducted on Bonalbo Station, NT (130 59’ S 1310 19'E) in April 2003 where native sucker re-growth invaded an improved pasture paddock. Three chemical products at two application rates were used with a herbicide wiper. The two application rates consisted of a single pass over the target plants and a double pass from both directions.
The three chemicals used were Glyphosate 450 (450 g/L Glyphosate), Grazon (100 g/L Picloram and 300 g/L Triclopyr) and Garlon (600 g/L Triclopyr). Each chemical was diluted with rain water and a 100 percent non-ionic wetter applied to the mix at 1 percent. The dilution rate for Glyphosate 450 was one part product to five parts of water. The Garlon and Grazon chemicals were diluted at one part product to 15 parts of water.
In February, 2004 Graslan pellets were applied to selected areas at Bonalbo, Kumbyechants (130 50’ S 1310 50' E) and Stray Creek (130 59’ S 1310 19' E) Stations. In November, 2004 Graslan was applied to an area at DDRF (130 59’ S 1310 19’ E) using rates of 10, 15, 20 and 25 kg/ha.
Areas of between 100 to 300 square metres with various species of re-growth were pegged and applied evenly with Graslan pellets by hand. Individual plants were marked and were applied with a measured amount of pellets each.
Results:
A single wipe of Glyphosate 450 (G1) controlled almost half of the blood wood (Eucalyptus latifolia) and killed three out of the four plant species of stringy bark (Eucalyptus tetrodonta) and broad-leaved carbeen
13 Pastoral
(Eucalyptus confertiflora). Ironwood (Erythrophleum chlorostachys) suckers showed signs of severe damage two weeks after wiping when leaves and stems turned black and nearly total leaf defoliation occurred; however all ironwood suckers later recovered.
Double wiping of Glyphosate 450 (G2) did not improve the control rate and gave similar results to the G1 treatment. Most ironwoods (Hakea arborescens) and (Grevillea mimosoides) could not be controlled. Half or more of the three Eucalyptus spp. were controlled with the G2 treatment.
The two Garlon treatments controlled very few suckers. No blood wood plants were controlled and only the odd suckers of kapok (Cochlospermum fraseri), sandpaper fig (Ficus opposita), Grevillea mimosoides and nut tree (Terminalia grandiflora) were affected. The results did not indicate any benefit of double wiping with Garlon compared with a single application.
The single treatment of Grazon controlled a number of suckers including most ironwood, blood woods, stringy barks and terminalias. Double wiping with Grazon controlled all species, except for one ironwood sucker, indicating that double wiping was worthwhile.
Graslan pellets that were applied at Bonalbo, Kumbyechants and Stray Creek Stations in February 2004 had varying results depending on the soil type, plant species and application rates. The first observation check 34 days after application found little or no effect on sucker re-growth in the areas applied with 10 and 15 kg/ha. The areas applied with 20 kg/ha showed signs of having more effect on most species including grass and broad leaf species.
The second observation in July 2004 showed considerably more effect on targets of re-growth particularly on black wattle (Acacia spp.) on Stray Creek and Eucalyptus spp. Cocky apple, Grevillea, sandpaper fig and the odd ironwood at the 15 and 20 kg/ha rates. Yellowing leaves and leaf loss with no sign of new growth apparent on the affected trees were noted.
The final observation in August 2005, at the Kumbyechants trial site showed that very few re-growth plant species were affected. Grasses at this site were not affected and there appeared to be only little effect on Hyptis.
At Bonalbo the areas applied at 10 kg/ha showed very little effect on most species including most Eucalyptus species, ironwood, Terminalia and Grevillea. Only cocky apple was successfully controlled. Application rates of 15 and 20 kg/ha did have a major effect on the native and improved grass species (sabi grass and various summer grasses) and most broad-leaf plants (native and introduced weeds - Hyptis and Sida). These areas had very little ground cover remaining compared with the non-treated areas. The effect on re-growth at 15 and 20 kg/ha was uneven, with some of each species dying, but not all.
At 15 kg/ha, all Brachychiton and Hakea plants were killed, 64 % of the Eucalyptus species and 38% of ironwood. At 20 kg/ha, only 50% of the Brachychiton plants were killed, 66% of the Eucalyptus species and 41 % of ironwood. All Terminalia, corkwood wattle and sandpaper fig were killed.
The majority of plants at both Stray Creek sites were black wattle and Wynn cassia. At both rates of 15kg/ha and 20 kg/ha, a 98% and 100% kill was obtained on black wattle and Wynn cassia, respectively.
Discussion:
The herbicide wiper will only affect the plants that it comes into contact with and the taller and larger the leaf area, the more chemical that will be transferred onto the target. As chemical translocation is often slow through the plants, final ratings should be made several months after application. The application of herbicides when plants were most actively growing and during a cooler part of the day may have improved results.
14 Technical Annual Report 2004-05
The large difference in height of the re-growth reduced the effectiveness of application particularly by not contacting the shorter plants effectively. The exact amount of chemical applied to each target is difficult to measure; however at 100 % foliage cover the application rate is around 40 L/ha.
The Kumbyechants soil is a loamy red earth and heavier compared to Bonalbo. The site received approximately 600 mm rainfall after application and had an estimated 6 to 8 tonnes/ha biomass of standing grass at the time of application, which may have reduced the effectiveness of the chemical.
The Bonalbo soil is an Oolloo type red earth and lighter than the Kumbyechants soil. It received 480 mm of rainfall after application of the chemical. Various grass and broad-leaf species were present and actively growing; however total biomass was much less (approximately 1 to 2 tonnes/ha) compared with the Kumbyechants sites. Several small plants of ironwood and Eucalyptus species had emerged in the 2004-05 wet season at most sites suggesting the chemical residue may not be active. The lack of grass and other plant species may be due to chemical poisoning and/or the frequency of animals (cattle and wallabies) targeting the sites to graze.
Stray Creek has a light sandy red earth and is a much lighter soil type than the other two sites. Rainfall and biomass were similar to that on Bonalbo with the majority of plants being Acacia and Wynn cassia.
The results of the trial indicate that the use of Graslan pellets at and above 15 kg/ha will affect improved pastures and will not control a number of re-growth native timbers on these soil types. Black wattle was the only species found at one site and Graslan was successful in controlling it at the expense of the Wynn cassia and grasses. The application of a lighter rate of Graslan pellets to this area may have been successful to control the wattle without sacrificing the pasture species.
The effectiveness of Graslan pellets on re-growth at DDRF is not yet known as the treatments were applied less than 12 months earlier and not enough time has elapsed to reveal the results. The last observation in June 2005 found that because the site had been slashed to a height of 400 mm, it was not possible to notice the effect. It was noted that buffel grass (Cenchrus ciliaris) had not been affected even at the higher rates of 20 and 25 kg/ha.
PROJECT: Pasture Species Evaluation under Grazing at DDRF
Project Officers: B. Lemcke, P. Shotton, L. Huth and DDRF Staff
Location: Douglas Daly Research Farm (DDRF)
Objectives:
To evaluate pasture species and mixtures under a continuous grazing regime on Blain soil at DDRF.
To determine their persistence, productivity and contribution to weight gain in cattle.
Background:
Promising pasture species are evaluated under grazing at DDRF to determine their long term potential in the Douglas Daly environment.
Method:
Pastures are grazed in 4 ha paddocks by five Brahman weaner steers per paddock (1.25 animals/ha). The exception is paddock 49, which had five extra animals to increase the stocking rate to 2.5 animals/ha to monitor the long term effects of heavy stocking rates on this productive buffel pasture. Steers are allotted to
15 Pastoral paddocks in June/July (post weaning) and remain in the grazing trial until the following June (almost 12 months).
Paddocks are top-dressed annually with a phosphorus-based fertiliser. This year, 50 kg/ha Pasture Generator (NPKS 0:15:0:18) was aerially spread on the paddocks. During the wet season, various weed control measures were undertaken where required, usually spot-spraying for broad-leaf weed control. Some grass-only paddocks are boom-sprayed with Starane®/2, 4-D or 2, 4-D/Brush Off ® mixtures if broad-leaf weeds become prominent. Urea was applied at 100 kg/ha to paddock 532 (split applications in January and early March) as a substitute for wet season block consumption.
New paddocks established: Paddock 42 Existing Wynn cassia pasture over-planted with Jarra grass. Paddocks 45, 48 and 534 were planted with extended Cunningham leucaena rows to the full length of the paddocks.
The animals were supplemented ad-lib with Uramol blocks during the dry season and with Phosrite blocks in the wet season. Intake was recorded monthly. Paddock 532 animals received no wet season block supplement, but urea was applied in the wet season to replace the block.
Cattle were weighed monthly, condition scored and the P8 (rump) fat was measured from January onwards until the end of the grazing season in June 2004.
Pasture composition and yield were assessed twice during the year; first in the early wet season, during December 2004 and then post-wet season, in April 2004.
Paddock 50 has four blocks of multiple plots of five legumes sown into an existing buffel grass stand during December 1999. It was grazed continuously throughout the period from July 2004 to June 2005 (see Pasture Species Evaluation under Grazing at DDRF - Paddock 50).
Paddock 48 contains three rows of Cunningham and three rows of cv. Taramba leucaena, which were slashed in November 2000 to a height of 30 cm and de-stocked until January 2001. In December 2001 and again in Jan 2004 the rows were slashed low. Stock remained in the paddock. Each leucaena row is half the paddock in length and before slashing, it was from 2.5 to 4m in height. Taramba was taller.
A new paddock (No. 42) was established in 2002 with Wynn cassia. It was treated for grass and broad-leaf weed control to maintain a high proportion of Wynn cassia. Grazing commenced in March 2002.
In 2003, another new paddock was added to the system (No. 41) which was sown with Tully and no stocking was allowed to ensure maximum establishment. Stocking commenced in mid Jan 2004.
In early December 2004, Paddock 42 was sown with Jarra grass, while maintaining Wynn cassia. It was then restocked in February 2005. Also in December, the half rows of leucaena were extended the full length of the paddock in Paddocks 45, 48 and 534.
16 Technical Annual Report 2004-05
Table 1. Mean cattle live-weight gains for each paddock (kg/head)
Paddock No. Pasture type July 04- Nov 04- April 05- Total Nov 04 April 05 June 05 July 04- Late dry Wet season Early dry June 05 39 Buffel/leucaena (five rows) 51.4 126.0 33.0 210.4 ** 40 Nunbank buffel 30.8 139.6 20.6 191.0 ** 41 Tully (B. humidicola) 25.0 109.2 -1.4 132.8 42 Wynn cassia/Jarra (post 13.0 103.0 41.8 157.8 February ‘05)* 43 Oolloo 37.6 115.8 31.8 185.2 44 Pangola 35.1 130.6 16.6 182.3 45 Pangola/leucaena 32.4 141.2 24.6 198.2 ** 46 Sabi 11.2 133.6 -9.6 135.2 47 Jarra -6.4 135.6 8.2 137.4 48 Sabi/leucaena 32.5 130.2 22.0 184.7 49 Buffel/tall variety 9.6 122.9 10.1 137.5 50 Buffel/legumes 20.0 131.6 16.4 160.7 51 Strickland/Wynn 25.2 144.0 17.4 186.6 ** 52 Arnhem/Oolloo 9.6 129.2 9.0 147.8 531 Buffel/sabi/blocks 20.0 122.0 14.8 156.8 532 Buffel/sabi/urea 15.0 111.1 20.5 146.6 533 Buffel/sabi/Wynn 32.2 140.8 10.6 183.6 534 Leucaena/buffel/sabi 21.0 125.8 9.8 156.6 535 Buffel/Oolloo 47.2 135.6 17.4 200.2 ** All paddocks Mean live-weight change 23.7 127.8 16.5 168.0 ** Mean weight gain above mean for all paddocks. * Cattle de-stocked from paddock from December 04 to February 05
Table 2. Mean cattle live-weight gains for the previous seven years (kg)
Year 1998-99 1999-00 2000-01 2001-02 2002-03 2003-04 2004-05 Live-weight gain 190.4 187.7 176.1 173.0 173.1 176.5 168.0
Paddock 49 has again achieved the highest production per hectare of all the paddocks without any sign of pasture deterioration. Total weight gain dropped from 387.5 kg/ha, 377 kg/ha, and 385 kg/ha in the last three years to 344 kg this year. Overall paddock means are lower this year than in all the last six years, most likely due to the late start to the wet. However, some paddocks have performed above expectation, such as the buffel/leucaena, the buffel/Oolloo and the pangola/leucaena. The presence of a legume appears to be the vital link to above average animal performance. Paddock 50 (legume/buffel) appears to have run its course with all legumes including Oolloo now down to very low proportions of the total forage available. Maldonado and blue pea have almost disappeared entirely from the pasture. Low levels of Wynn cassia, Verano and Oolloo still remain, but at nowhere near their previous levels.
De-stocking of the Oolloo/buffel paddock from April to June last year for the Oolloo flowering period did not appear to be required this year as there was more than adequate flowering and pod-setting. This will continue to be monitored. The management practice of splitting the leucaena paddock into two halves and feeding each block alternately on a monthly rotation appears to be a good move after the performance of steers in Paddock 39. Strickland continues to out-perform Jarra, but the inclusion this year of Jarra in Paddock 42 will help to confirm this observation over the next few years. The inclusion of Jarra with Wynn cassia was carried out this wet as there seemed to be no point in continuing the poor performance of cattle on Wynn cassia alone. The early start to the dry season also resulted in some weight losses on some paddocks during June, which is rare in most years.
17 Pastoral
Block consumption
Uramol was supplied from 07/07/04 to 02/12/04, and Phosrite from 22/11/04 to 16/06/05 (de-stocking of all paddocks except No. 532 for the wet).
Table 3. Consumption of supplementary blocks
Paddock Variety/species Dry season: Uramol® Wet season: Phosrite® No. consumption (143 days) consumption (206 days) g/head/day g/head/day 39 Buffel/leucaena (five 84 79 full length rows) 40 Nunbank/buffel 53 88 41 Tully (B. humidicola) 69 49 42 Wynn cassia/Jarra 56 90 43 Oolloo 55 67 44 Pangola 51 19 45 Pangola/leucaena 108 18 46 Sabi 105 37 47 Jarra 84 70 48 Sabi/leucaena 84 62 49 Buffel (tall variety) 70 74 double stocking rate 50 Buffel/legumes 106 68 51 Strickland/Wynn 105 72 52 Arnhem/Oolloo 82 61 531 Buffel/sabi/blocks 84 99 532 Buffel/sabi/urea 106 Not given 533 Buffel/sabi/Wynn 84 98 534 Leucaena/buffel/sabi 56 65 535 Buffel/Oolloo 84 91 All paddocks 80.3 68.2
Consumption rates in comparison with last year are lower for both Uramol® and Phosrite®. Over seven years, consumption is at the lower end of the range for Uramol (range 78-134 g) and the lowest for Phosrite (previous range 72-119 g). Group variation is less than last year with consumption rates of Phosrite on pangola pastures being again extremely low.
The comparison between N fertilisation of buffel vs. wet season blocks will continue for a few more seasons to see if the N effect is cumulative. The yearly difference in the first year was 23 kg live-weight gain/head in favour of the block-fed group (Paddock 531 vs. Paddock 532). This year the difference was less (10 kg per head) and we would expect this trend to continue over the next few years as N builds up in the soil through application and recycling
18 Technical Annual Report 2004-05
PROJECT: Feeding Trials, Berrimah Farm
Project Officers: B. Lemcke, R. Kelly, R. Eastick, N. Hartley, G. Schultz and L. Huth
Location: Berrimah Farm
Objectives:
To evaluate the supplement block response level in cattle fed pelleted rations.
To determine the value of irrigated hay from DDRF compared with Cavalcade hay for yearling cattle.
Background:
Trial 1: The value of supplementary blocks for cattle fed pellets
In past trials stock-feed pellets were used to feed cattle, with free access to Phosrite® mineral block supplement. The value of the block supplement in terms of live-weight gain needed to be quantified.
Trial 2: Comparison between cattle fed fine-cut Rhodes, forage sorghum and Cavalcade hay
Fine-cut Rhodes and forage sorghum are currently grown under irrigation at DDRF during the dry season as rotation crops with peanuts or as stand-alone crops for producing good quality hay. This will help to defray the capital cost of irrigation equipment and will also supply a nitrogen-scavenging plant to follow a legume rotation. There was a need to assess the value of feeding cattle, to determine if the cost of producing the hay was justified economically.
Method:
Groups of six yearling Brahman steers were used in each of the two trials, with two groups per treatment. The animals weighed between 295-335 kg at the start of Trial 1. They were then weighed weekly at the same time in the morning.
Trial 1
Two groups were fed shipping pellets alone in separate pens and the other two groups were fed pellets but they also had access to Phosrite ® supplement blocks. Water was supplied in automatic drinking bowls. Pellet consumption was recorded daily and the blocks were weighed weekly to determine mean daily consumption. Sufficient pellets were provided to ensure a surplus was available in the trough at all times. The pellets were made of a mixture of Wynn cassia and Calopo. As they were left over from previous trials, some deterioration may have occurred during the wet season. When those were finished, pellets made from Cavalcade hay from DDRF were used. The animals were fed for four weeks.
Trial 2.
Two groups of animals were fed each variety of hay on a daily or twice daily basis. Racks were topped up in the afternoon if required to last until the next morning. The animals were fed for five weeks. Drinking water was available all the time.
19 Pastoral
Results:
Trial 1
The supplemented groups gained more weight, ate more feed, and consumed blocks at an average rate of 92.7 g/head/day. The supplemented groups gained 117 g/head/day more than the un-supplemented groups. The daily cost of the supplement at the above rate of consumption was about 9.7c/day whilst the value of the weight gain was about 18.7c/day ($1.60/kg live-weight at current export prices). There was a very significant variation between animals within each treatment depending on their individual intake. This may be a dominance problem or stress related due to confinement in the yards.
Discussion:
One steer had to be removed from the trial because it refused to eat and another four also lost weight between the start and completion of feeding. These animals may be typical of Brahmans which never seem to settle down in a yard. There were also large differences between animals within the one group in live- weight gain, probably due to intake differences. The consumption rate of the blocks was much lower than in the previous year, when rates were 200-320 g/head/day and live-weight gains were much higher. In the first week, feed consumption was considerably low due to Calopo pellets. Consumption increased once Cavalcade pellets replaced Calopo pellets. It appears that some weight gain can be achieved by providing blocks to confined animals which increased intake slightly -by 5.5%- and live-weight gain by 50%, in this instance. This rate of gain would not be expected to be maintained.
Trial 2
Table 1. Results from feeding the three hay types Pen 1 Pen 2 Pen 3 Pen 4 Pen 5 Pen 6 Sorghum Cavalcade Sorghum Rhodes Cavalcade Rhodes Block 44.3 100.0 50.0 119.5 76.7 68.1 consumption (g/head/day) Hay 6.61 7.63 7.31 7.00 7.35 8.09 consumption (kg/head/day) Mean daily 440.5 730.2 476.2 952.4 531.8 746.0 cattle LWG (g/head/day) Mean of LWG 631.0 458.4 849.2 treatment g/head/day reps Block 88.4 47.2 93.8 g/head/day Hay 6.96 7.49 7.70 kg/head/ day
Discussion:
Block consumption was low compared with last year and similar to that in the previous pellet trial. Forage sorghum hay, while eaten only marginally less (DM intake), produced lower live-weight gains in the animals. In terms of live-weight gain, Cavalcade was 38% better than the forage sorghum hay, whilst the Rhodes grass hay was 85% better than the forage sorghum. Cavalcade hay was a rather late-cut and poorer than the other two irrigated hays. They had the added quality of being cut and baled during the dry season. Some Cavalcade bales were mouldy and had to be cut to remove the mouldy sections to keep palatability as high as possible. Better results would be expected from a better quality, earlier-cut Cavalcade. Compared with other hays last year, the irrigated Rhodes grass proved to be much superior. Its lightness and tensile strength proved to be a problem when making shipping pellets from the hay. It may be suitable for using in
20 Technical Annual Report 2004-05 cubes with the right milling equipment. Forage sorghum, whilst readily eaten, did not produce as high weight gains, although 450 g/head/day gain was still a pretty good result. Many locally grown grass hays are barely able to even maintain animal body weight. The cost of irrigated production of forage sorghum (fertilizers and water) would definitely give wet season-grown Cavalcade an advantage as a cattle feed. More details are provided in the Irrigation Group report.
PROJECT: Assessment of Multibreed Composites and Improvement of Brahman Cattle
Project Officers: G. Jayawardhana, P. O'Brien, S. Reed, C. Hazel, S. Izod, R. Muirhead, K. McCosker, T. Bidgood, B. Lemcke, E. Cox, L. Humphries, J. Stevens and D. Cumberland
Location: Douglas Daly Research Farm (DDRF), Beatrice Hill Farm (BHF) and Victoria River Research Station (VRRS)
Objectives:
To measure the relative growth, reproductive performance and carcass characteristics of the interbred progeny of some tropically adapted multi-breed crossbred bulls mated to Brahman cows, compared with the progeny of Brahman bulls mated to Brahman cows.
To maximise Brahman performance for reproduction and growth while minimising mature weight.
Background:
Multi-breed composites retain larger amounts of heterosis (hybrid vigour) in future generations than do the old style two-breed animals such as Droughtmaster, Braford and Charbray. They also combine the good points of the more different cattle types. Most large cattle companies such as NAPCO, AACo and Stanbroke are shifting to multi-breed composites. This project compares a composite suitable for the Top End with improved Brahmans selected for growth and reproduction.
Method:
A composite of 56.3% Brahman, 12.5% Africander, 12.5% Tuli, 6.3% Shorthorn, 6.3% Hereford and 6.3% Charolais is being compared with the Brahman. This cross gives a mix that is 81% tropically-adapted with 19% unadapted Bos taurus and can be expected to retain about 64% of heterosis in the second generation onwards. They resulted from crossing half Belmont Red, quarter Tuli, and quarter Charbray bulls (from Geoff Maynard’s Mt Eugene stud in Queensland) to Brahman cows. The cows are kept at VRRS, while heifers up to three years of age are kept at DDRF and steers are kept at DDRF and BHF. Animals are not treated for worms, ticks or flies. The composites and comparison Brahman bulls are selected on weight, testicle size and percentage normal sperm at yearling, while heifers are selected on pregnancy. They are all multiple sire- mated, using DNA typing to identify sires for recording in Group Breedplan, which is the Australia-wide genetic evaluation system. Breedplan is used to assess progress, rather than as a within herd selection tool. This allows for the program to be replicated in more extensive herds.
Results:
The effect of the Brahman improvement program is shown by the average days to calving in cows and scrotal circumference in bulls, which are reproduction traits. Estimated breeding values (EBV) for DDRF Brahmans are the best of all the Brahman group herds in Breedplan. The 400-day weight EBV are slightly lower than the breed average (a consequence of the high level of selection for reproductive traits) while
21 Pastoral mature cow weight is kept relatively low, since large cows require more feed. The Brahman breed average for weight has improved significantly but at the expense of an increase in mature cow weight and no increase in scrotal circumference and days to calving. This is a worrying trend for the Brahman breed as reproduction has been shown to be more important economically than growth, and large mature cows will not re-breed in harsh environments.
Another indicator became clear when industry yearling Brahmans were mated at DDRF. Pregnancy in industry heifers at a comparable weight range (220 to 290 kg) was 28% at an average joining weight of 256 kg compared with a 50% pregnancy rate for the DDRF yearling Brahmans at an average joining weight of 250 kg. This is almost double the industry pregnancy rate and shows the importance of selection for fertility.
However, the success of this program in a small herd (250 females) over a ten-year period shows that very rapid improvement will be possible in the large NT herds if these methods are adopted. Work by Eler et al. in Brazil in 2004 indicates that the heritability of reproduction is a lot higher than is generally accepted in Australia - 69% heritability for yearling pregnancy in Nellore cattle compared with Australian estimates of 7 to 15%.
The fertility in composites is even better than that in the selected Brahmans (see table below). In the weight range shown above, the yearling composite pregnancy was 78% at an average joining weight of 248 kg. This is 28% better than the DDRF heifers and 50% better than industry heifers.
Table 1. Preliminary results on average production of Brahman and composite cattle
Brahmans (no.) Composites (no.) Difference Birth weight 28.4 kg (259) 1st cross - 27.9 kg -0.5 kg 26.6 kg (82) (233) 0.8 kg 2nd cross - 27.4 kg(127) Weaning weight 188.1 kg (316) 1st cross-195.8 kg 329) 7.7 kg 174.6 kg (134) 2ndcross-179.3 kg 4.8 kg (150) Yearling (400-day) 199.0 kg (317) 208.1 kg (327) 9.1 kg weight Yearling (400-day) 23.1 cm (107) 26.1 cm (109) 3.0 cm testicle size Normal sperm (%) at 7.7% (107) 25.2% (109) 17.5% (three times the yearling % normal of Brahmans) Yearling pregnancy 35.5% (60/169) 61.4% (124/202) 25.9% Pregnancy rate of 31.4% (11/35) 60.2% (47/78) 30.8% (nearly double lactating two-year old the Brahmans) animals Pregnancy rate of 72.0 % (54/75) 74.0% (54/73) 2.0% lactating three-year old animals Pregnancy rate of 42.8% (12/28) 67.7% (21/31) 24.9% lactating four-year old animals Two-year steer weight 390.0 kg (54) 415.9 kg (51) 25.9 kg Carcass weight 227.8 kg (27) 237.2 kg (25) 9.4 kg Eye muscle area 73.3 cm² (27) 78.4 cm² (25) 5.1 cm²
The first cross composites were born lighter than the Brahmans but gained weight faster. Their weight and reproduction figures have been consistently superior to those of the Brahmans. Initial carcass figures indicate that eye muscle area per kg carcass weight was superior in the composites. The composites also have good resistance to ticks and flies.
22 Technical Annual Report 2004-05
The first of the second-generation data is presented here which shows second cross composites were heavier at birth and at weaning. The second-generation performance is more important than that of the first cross as the loss of heterosis in a composite occurs between the first and second generations.
PROJECT: Reproduction Management Trials on Commercial Properties - Florina/Camp Creek Wet Season Weaning Trial
Project Officers: G. Jayawardhana, J. Blake (owner of Florina and Camp Creek), Station Staff on Florina and Camp Creek
Location: Florina and Camp Creek Stations
Objectives:
To record the results of innovative programs conducted on private properties which may be useful to the rest of the industry.
To examine the effects of a modified weaning and joining program on reproduction in cows and growth and mortality in calves.
Background:
Some Queensland producers with innovative cattle management programs have been advocating a weaning and joining program that is significantly different from the general industry practice. They join females to bulls from October to January, which results in calving in the dry season, from July to October. They wean from November to February. They plan to encourage efficient rumen development in weaners at the time when best feed is available, which is in the wet season. Cows go through the wet season without calves suckling them and are thus dry and in good condition during pregnancy tests. This makes it easy to sell empty cows at that time.
This program commenced at Florina last year, but no records were taken. The cows were tested for pregnancy in April 2004. All cows that were empty or under two and a half months pregnant, were culled. In future, data will be recorded from Camp Creek where the cattle are now located since Florina Station has been sold.
Method:
This trial commenced in December 2004. All the calves were kept in the yards for three days and were handled using Bud Williams’ Low Stress Stock Handling methods. Heavy rains over this period and a very limited shelter of tarpaulin made it difficult to keep weaner pellets dry. Due to the management method, calves were eating hay and pellets during this period. They were then divided into two groups, those over 80 kg and those under 80 kg. They were all grazed on improved pasture and the larger weaners were given monensin mixed with molasses and a pure kynophos loose-mix in the open. The smaller weaners were given weaner pellets containing monensin, monensin molasses mix and kynophos in a covered shed in the paddock. In total 3360 kg of calf pellets, 0.5 kg of Rumensin (monensin) and 600 litres of molasses were fed at a total cost of $2493 ($10 per animal). The cows were put separately on native pasture with pure kynophos as a loose mix.
23 Pastoral
Table 1. Results of the study
Average Minimum Maximum weight weight weight Weaning time (30/12/04) 87 kg 46 kg 155 kg Marking and dehorning time (01/08/05) 147 kg 77 kg 258 kg Gain 60 kg 24.5 kg 103 kg
There were three deaths out of 249, which is 1.2%. The average weaning weight of the dead calves was 62 kg which indicates that they were at the lighter end of the weaner weights. Nonetheless, this is very low mortality for calves weaned at these weights. It does not include mortalities due to dehorning and castration which were conducted at a later date. Late marking was due to logistical issues at Florina as branding should have been done in the first dry time after weaning. The pregnancy rate of the cows that were dry at the pregnancy test in June 2005 (most of which had weaners removed in December) was 94%. The first calf heifer pregnancy rate was 77%. Six wet adult cows were not mustered during the December weaning and three of them were pregnant. All three wet first calf heifers were not pregnant. Though these numbers are too small to act as a control, they indicate the effect of the early wean.
Discussion:
On initial results this weaning method appears quite promising where wet season mustering is possible. The pregnancy rates were very high for a property in the Katherine region and weaner performance was acceptable.
However, in the opinion of project officers, low stress stock handling was the main factor that kept weaner mortalities down to these extremely low levels. Weaning in the middle of a monsoon without shelter would be a recipe for disaster unless animals are not stressed and are hence eating.
PROJECT: Reproduction Management Advisory, Training and Maintenance of a Semen Vat
Project Officer: G. Jayawardhana
Location: Berrimah Research Farm and Private Properties
Objectives:
To train and advise NT pastoralists on reproductive/management techniques to improve the profitability of animal industries.
To maintain a liquid nitrogen vat to store and dispatch semen to facilitate artificial insemination in the NT.
Result:
A pregnancy testing school was held at Newcastle Waters Station when 12 people were trained.
Lectures and practical sessions were held in 2004at the Barkly Herd Management Course at Alexandria and Brunette Downs Stations and in 2005 at Helen Springs and Avon Downs Stations.
Property visits and/or phone advice were given to Ban Ban, Bonalbo, Camp Creek, Cedar Park, Ceres Downs, Elsey West, Ferguson River, Florina, the Heytesbury Pastoral Company, Hodgson River, Ironstone, Jindare, Maneroo, Marrakai, McKinlay River, Melaleuca, Mt Keppler, Mt Ringwood, Newcastle Waters, Old
24 Technical Annual Report 2004-05
Mt Bundy, Phoenix Genetics, the Pines, Stylo, Taminmin High School, Theyona, Vermelha, Whynot, Willeroo and Wollogarang.
The semen vat containing about 21 000 doses of cattle and buffalo semen was maintained. It belongs to DPIFM and 28 producers. Semen was dispatched for seven artificial insemination programs.
25 Pastoral
Program: Improved Pasture, Hay and Seed Production
Sub-program: Pasture Development
Objective:
To expand the industry base through increasing areas under pasture and improving industry skills and experience in managing pastures.
Outcomes:
An expanded industry through increased pasture production.
Continued support of forage research and demonstration programs to increase hay supply to the emerging forage cube industry.
Overview – 2004-05
The 2004-05 wet season - October to June
The wet season was poor for most of the district. Significant rainfall events were generally rare and isolated at most recording sites in the Darwin and rural, and Darwin-Daly areas.
Until the second week of November, most of the rain was coastal, while inland areas were extremely dry. After mid November, rain events were more regular, but still isolated in location and timing. There were no prolonged monsoonal periods during the wet season, and only five days had widespread significant falls. Most areas received two to three significant falls per month between December and March.
The number of rainy days was two thirds of that in the previous season. Most sites received 500 mm to 800 mm less rain in significant falls than in the previous wet season.
Pasture yields were reduced across the district, except for some hay and fodder crops which received spaced falls at optimal times. The isolated erratic falls kept pastures green, but did not produce normal dry matter yields.
Floodplains did not flood for long this wet season, and were dry enough to access earlier than in most years.
Unless there are significant falls of rain early next wet season, there may be a severe feed shortage on both upland and floodplain areas at the end of the year.
Demand for pasture and seed extension/information continued at high levels during the year, with the number of enquires up slightly on last year, reaching 464 for the year.
Arthur Cameron presented an invited paper on the success of Cavalcade and Bundey in the Northern Territory at the International Grassland Congress in Ireland in June 2005.
Albert Simonato and Arthur Cameron developed and presented a sampling course, and developed testing methods to facilitate the sale of Northern Territory fodder cubes in Western Australia.
A survey showed that total hay production was up by approximately 14 000 tonnes to 52 890 tonnes and seed production was up by 164 tonnes to 305.1 tonnes.
26 Technical Annual Report 2004-05
The Section facilitated the production of 1.5 tonnes of pre-basic seed of Katherine pearl millet. The seed will be available for producers to again grow the popular cultivar seed for sale.
Arthur Cameron appeared in the ABC TV Catalyst program on gamba grass which was screened on 16 September 2004.
The Seed Laboratory has been charging for services since 1 July 2004.
Our output has been limited this year due to the secondment of Greg Hore to the Grapevines program and Barbara Ross to DIPE, which was followed by her resignation from the NTPS.
PROJECT: Seed Increase of Early Generation Seed of Released Pasture Cultivars
Project Officer: A. Cameron
Location: Paddocks 8 and 9 Berrimah Farm
Objective:
To evaluate new lines in a confined non-grazed environment.
To bulk-up seed from promising lines for further evaluation.
To bulk up early generation seed of pasture cultivars released in the NT.
Method:
Small areas of cultivars released in the Northern Territory are maintained in Paddocks 8 and 9 at Berrimah Farm, Coastal Plains Horticulture Farm (CPHF) and at Katherine Research Station. Seed harvests are organised as required to ensure that fresh early generation seed is available.
Seed crops of annual species are grown and harvested as required.
Results:
A pre-basic seed area of Cavalcade in the netted area at CPHF is yet to be harvested.
Over 1.5 t of pre-basic seed of Katherine pearl millet was produced from a crop on a commercial property in the Katherine area.
27 Pastoral
PROJECT: Predicting Environmental Weed Risk of Exotic Grasses in Northern Australia
Project Officers: Dr. R. van Klinken (CSIRO), C. Wilson (DNRETA), Dr F. D. Panetta (QDNRM), B. Cook (QDPI&F) and A. Cameron
Location: Brisbane and Darwin
Objectives:
To identify and rank current and impending grass-weed threats to northern Australia and identify benign beneficial species
To identify combinations of plant/environmental/cultural factors which are favourable to local dominance of weedy grass species in natural ecosystems
To develop a landscape specific weed risk assessment for grasses.
Background:
Exotic grasses are emerging as one of the greatest threats to northern Australian landscapes, both to the environment and the pastoral industry. In contrast, relatively few exotic grasses that were evaluated for agricultural purposes in northern Australia have survived for six months or more, and even fewer have been commercialised. Using the existing body of world literature, and leading edge modelling techniques, this project seeks to explore the reasons for the ecological success of relatively few exotic grasses in an attempt to more accurately predict the risk of weed grasses in northern Australia.
A broader significance of this work, in conjunction with other Weeds CRC projects, is to determine how well the existing AQIS weed risk assessment (WRA) applies to grasses. Can WRA models be further refined to take into account weediness within different landscapes? Can WRA be used to help resolve serious issues of conflict?
Method:
A comprehensive database has been developed listing all exotic grasses known to have naturalised in northern Australia and detailing traits for each species such as distribution, weediness, beneficial properties, life history and physiology. The database relied on a literature review and knowledge of grass specialists throughout northern Australia.
For a subset of exotic grasses that are already widely distributed in Australia, but that differ in their weediness, sets of “best bet” predictive characters will be tested against known weediness and the predictions of the existing WRA. Workshops will allow input from other collaborators, such as weed scientists, pasture researchers and practitioners for the selection of predictive characters.
A WRA type method for predicting weediness of exotic grasses across the different landscapes in northern Australia will be developed and validated. Available grass traits, spatial landscape data such as climate and soils, and modelling/spatial analysis tools will be used
Results:
A database listing over exotic 200 grass accessions in northern Australia has been compiled. Information about each of these grasses has been added to the database.
A PhD student is working on the modelling aspects of the project.
28 Technical Annual Report 2004-05
PROJECT: Seed Testing Laboratory
Project Officers: A. Simonato, L. Simington and A. Cameron
Location: Berrimah Farm
Objective
To provide an accurate and reliable seed testing service to the pastoral industry, Government and the public in the NT.
During the year 173 consignments were submitted for testing.
The following tests were carried out on the submitted lots.
Type No. of tests Certification 6 Purity 19 Germination 149 Bulk search 9 Quarantine inspection 17 Quarantine identification 6 Comparative test 3 Tetrazolium test 2 Import examination international 1 Export examination interstate 9 Seed count 0 Identifications 4 Audit samples 1 Total 226
Other seeds matters
Seed certification applications were made for 101 hectares during the 2004-05 wet season.
Certification was provided for 38.55 tonnes of Cavalcade seed in late 2004.
Maldonado seed was sold to Above Capricorn Technologies for use in an overseas project.
Pre-basic Bundey seed (50 kg) was sold to a Top End producer.
Albert Simonato completed the Australian Round Robin Identification Comparative Test.
Albert Simonato and Arthur Cameron developed and presented a sampling course, and developed testing methods to facilitate the sale of NT fodder cubes in Western Australia.
The Seed Laboratory introduced charges for its services on 1 July 2004.
Lisa Simington adapted the existing seed testing database, enabling it to calculate, record and report the laboratory charges. Improvements were also made to the database’s search facility.
Lisa Simington completed the development of an Access database for the Seed Reference Collection. The database now contains information relating to 1973 seed lots. This includes data for the 97 new reference samples that were processed and added to the collection in 2004-05.
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Albert Simonato and Arthur Cameron conducted seed sampling refresher courses for six departmental and industry staff.
Albert Simonato and Arthur Cameron conducted seed sampling courses for four departmental and industry staff.
PROJECT: Pasture Development Extension
Project Officer: A. Cameron, A. Simonato and L. Simington
Location: Berrimah Farm
Objectives:
To maintain extension services to industry.
To assist industry to increase and manage areas of improved pastures.
To continue producing high quality seed.
During the year the Section received 464 individual requests for advice from a range of customers, including primary producers, departmental staff, staff from other Departments, agribusiness, students and others, including a number from interstate and overseas. The largest groups were departmental staff (163) and primary producers (161). Most requests were about pasture species (114), seed testing (101) and seeds and planting material (86). Requests were received through the telephone (267), visits (122) and email (74).
Specific extension activities included:
• Show judging: Arthur Cameron judged five properties for the Royal Darwin Show Farm and Pastoral Competition. • The Section is continuing a survey/removal demonstration on major roads in the Top End to show that gamba grass can be controlled. There has been limited input in this demonstration this year.
NT hay and seed production 2004
A survey was conducted to estimate hay and seed production in the NT in 2004. These figures include the significant amount of mulching hay made in the Darwin Rural area, and the hay equivalent of silage made on a number of Top End properties. The figures are shown in Table 1.
Both hay and seed production increased this year. Total hay production was up by approximately 14 000 tonnes to 52 890 tonnes, and seed production was up by 164 tonnes to 305.1 tonnes. The estimated value of hay produced is $9.74 million and seed $1.16 million.
These figures represent most of the production in the NT in 2004.
30 Technical Annual Report 2004-05
Table 1. Hay and seed production in the NT by district
Feed hay Mulch hay Seed District (tonnes) (tonnes) (tonnes) Adelaide River 1070 Alice and Barkly 8350 0.6 Batchelor 390 Darwin 2070 570 Darwin River 230 1930 Douglas Daly 11 220 5.0 DPIFM 730 4.3 Katherine and VRD 25 610 294.9 Mary River 720 Other 0.9 Total 50 390 2500 305.1
These figures were compiled by Arthur Cameron with the assistance of Departmental Officers Ruth Allan (Tennant Creek), Ben Beumer (Darwin), Andrew Bubb (Tennant Creek), Sarah Fea (Katherine) and Phil Hausler (Darwin).
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Program: Irrigation Production
Sub-program: Douglas Daly - Irrigated Crops
PROJECT: Evaluation of Irrigated Fodders at Douglas Daly Research Farm - Continuing Project
Project Officers: F. O'Gara, C. Collins, P. Shotton and DDRF Farm Staff
Location: Douglas Daly Research Farm (DDRF)
Objective:
To determine the yield potential and agronomic requirements of various irrigated forage crops under centre pivot irrigation and assess their suitability as rotational crops with peanuts in the Daly basin.
Background:
There is a need to evaluate a range of field crops and identify suitable varieties for irrigated production and rotation with peanuts in the Katherine Daly basin. Some of the major limitations to the development of an irrigated field crop industry are the shortage of suitable rotation crops and markets, and the relatively high cost of production compared with other farming areas.
Although peanuts have been successfully produced using centre pivot irrigation, there is a need for a viable rotation crop in the farming system. The value of the area producing peanuts has declined recently due to low returns. Maize was evaluated in 2000-03as a rotation crop at DDRF. Grain yields of 9 to 12.7 t/ha and silage yields of 40 t/ha were achieved under irrigation on Douglas Daly Blain soils. Under commercial conditions, grain yields of 9 to 10 t/ha should be achievable using the best lines.
There is continuing interest in the production of high quality hay for export and for the live cattle export trade. Hay, especially from grasses, produced in the wet-season has a low nutritional value and is unsuitable for export. Dry season irrigation offers the opportunity to produce high quality hay suitable for the export trade. It is necessary to evaluate different fodder species and varieties to determine agronomic requirements, production costs and quality traits. Finding viable crops to rotate with peanuts will benefit the farming system and assist with pest and disease management. Non replicated evaluations have been conducted since 2003 to assess maize silage, forage sorghum and Rhodes grass for yield and commercial potential under irrigation at DDRF. Four forage sorghum cultivars, Fine-cut Rhodes grass and lucerne were further evaluated in 2004- 05 seasons.
Rhodes grass
This is the third season for the evaluation of “Fine cut” Rhodes grass under irrigation. The plot was first sown on irrigation circle 2 (10 ha pivot) on 25 March, 2003. The seed was dropped onto a finely prepared seedbed at the rate of about 20 kg/ha. The high seeding rate was necessary to ensure good establishment in an area which had a large seed bank of summer grasses. Summer grasses cannot be controlled in a crop of Rhodes grass. Therefore competition is the only management option.
32 Technical Annual Report 2004-05
Table 1. Irrigated sorghum and Rhodes grass hay yields at DDRF during the first year of establishment – 2003
Harvest Rhodes Grass Jumbo Sweet Jumbo Yield* Protein Energy Digest. Yield* Protein Energy Digest. (t/ha) 16/06/2003 13 weeks 6.4 10.8 8.5 59.5 8.6 9.9 8.7 61.1 11/08/2003 8 weeks 8.3 10.7 9 62.5 10.3 02/10/2003 8 weeks 6.2 7.3 7.8 55.2 6.3 5.5 9.4 8.7 61 17/11/2003 6.5 weeks 5.6 6.2 8.8 Dry season total 03 26.5 31.4 14.3 22/04/2004 9.9 11.8 08/06/2004 5.42 4.1 Energy: MegaJoules/kg of dry matter Digestibility:% dry matter digestibility Protein:crude protein (nitrogen x 6.25) Feed analysis by Feedtest, Department of Primary Industries Victoria * Indicates hay yield not dry matter
Table 2. Nutrient concentration of various irrigated fodders at DDRF – 2003
Nutrient concentration in different forages and amounts removed (kg/tonne) dry matter Crop N P K S Ca Mg Cu Zn Fe B % % % % % % ppm ppm ppm ppm Rhodes 1.35 0.16 2.54 0.22 0.33 0.33 8 69 81 3 kg removed/t 13.5 1.6 25.4 2.2 3.3 3.3 0.008 0.069 0.081 0.003 F. Sorghum 1.96 0.2 2.53 0.13 0.37 0.38 7 98 136 3 kg removed/t 19.6 2 25.3 1.3 3.7 3.8 0.007 0.098 0.136 0.003 Maize stover* 1.14 0.11 1.56 0.11 0.44 0.24 12 84 90 12 kg removed/t* 11.4 1.1 15.6 1.1 4.4 2.4 0.012 0.084 0.09 0.012 *Does not include nutrients taken off in grain
Forage sorghum vs. Rhodes grass
In the initial season, in 2003, Rhodes grass was harvested four times and was compared with forage sorghum (cv Jumbo). Yields from sorghum were higher than those from Rhodes grass by almost 5 t/ha over the season (see Table 1).
In the 2004 (second year) season, ratoon crops of Fine-cut Rhodes grass and Sweet Jumbo forage sorghum were compared under similar management inputs. The forage sorghum stand declined in plant population through the season, which was reflected in reduced yields. Its population declined to about half of what is required for optimum productivity. The sorghum was progressively invaded by Rhodes grass and other non- productive summer grasses.
The Rhodes grass stand has maintained its density and vigour, and achieved a yield 36% higher than in the first year. This is largely due to the fact that the stand was already established and an additional harvest was possible. A total of 36 t/ha of Rhodes grass hay was produced over five harvests compared with about 17 t/ha of Sweet Jumbo forage sorghum.
What was apparent during this evaluation was that forage sorghum did not ratoon well and would need to be sown each season to maintain optimum productivity under irrigation. Rhodes grass on the other hand maintained its density and productivity and could be successfully held over from one season to the next. Figure 1 shows the yields during the second year for forage sorghum and Rhodes grass.
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Figure 1. Irrigated forage sorghum and Rhodes grass hay yields in the second year at DDRF (2004)
2004 fodder evaluations
Forage sorghum varieties
Four different Sudan grass hybrids were sown at DDRF in the 2004 dry season in a non-replicated evaluation. The varieties were Sweet Jumbo, Betta Graze, Superdan and Cow Pow. Between 2 and 3 hectares of each variety were established and harvested using a commercial mower-conditioner and round baler. The varieties were irrigated by centre pivot and received between 8 and 10 ML of water/ha.
Sweet Jumbo and Cow Pow are late-flowering sorghum x Sudan grass hybrids which have medium stem thickness and re-grow well after cutting. Betta Graze is a traditional (shorter season) sorghum x Sudan grass hybrid which is recommended for both hay-making and grazing. Superdan is a hybrid Sudan grass with fine stems and an intermediate flowering habit, that is, shorter than Sweet Jumbo or Cow Pow type forages.
The forages were planted on 23 April, 2004 in a fully cultivated seedbed. Fertiliser was applied pre plant and consisted of 230 kg/ha of Emerge® (43 kg/ha nitrogen, 30 kg/ha phosphorus, 22 kg/ha sulphur) and 153 kg/ha of muriate of potash (76.5 kg/ha of potassium). Urea was top-dressed at 125 kg/ha (57 kg/ha nitrogen) on 17 May. The first harvest was on 18 June, eight weeks after planting.
Three machine harvests and one hand harvest were done in early December (see Figure 2). Approximately 125 to 150 kg/ha of urea (57 – 69 kg/ha of nitrogen) was applied after each machine harvest. Due to the different seed sizes, the forages went out at different rates which resulted in different populations. Despite this, field establishment varied greatly between varieties. Betta Graze had the highest field establishment at 85% while Cow-Pow had the lowest at only 41%.
34 Technical Annual Report 2004-05
Table 3. Seed size, sowing rates and field establishment of forages Variety Average Sowing rate Established plant Field establishment seeds/kg kg/ha population/ha %* Cow-Pow 40 000 31.3 493 000 41.5 SuperDan 69 000 24.5 866 000 53.9 Betta Graze 30 700 26.8 666 000 85.3 Sweet Jumbo 40 000 41.6 1 140 000 72.0 *Calculated using 95% minimum germination as indicated on bags
Cow-Pow had the lowest plant population due to an establishment of 41%. Despite this Cow-Pow yielded as well as the other forages. Due to the variation in soil type and establishment rates between plots, no single variety was superior to the others. Management problems with the irrigation system resulted in lower watering and nutritional input than optimum. This was reflected in the lower than expected yield. The cutting interval (time from one harvest to the next) was too long and resulted in fewer harvests, lower quality and lower potential yield.
Table 4. Quality analysis of forages (June 2004*)
Variety Crude protein Neutral Metabolisable Dry matter (%) detergent fibre energy digestibility (%) (MJ/kg) (%) Cow-Pow 8.8 68.0 7.8 54.9 SuperDan 13.0 69.4 8.3 58.6 Betta Graze 8.2 73.7 6.9 49.6 Sweet Jumbo 8.4 - 12.1 64.7 - 71.6 7.1 – 8.7 50.5 – 61.0 *Conducted by FeedTest® Dept. Primary Industries, Victoria
Discussion:
While this evaluation was not conducted under ideal conditions, it revealed that achieving optimum forage sorghum populations can be difficult. High seeding rates are necessary to achieve sufficient plant numbers. Establishment of 40 to 50% is poor and usually results in inferior stands. Rolling to achieve better seed-soil contact may improve establishment on Blain soils and should be investigated. Dense uniform plant stands are required to achieve viable yields of forage under irrigation. However it is interesting to note that Cow- Pow, with the lowest plant population in this evaluation, produced the second highest yield. This is probably due to other factors such as stand uniformity, persistence and soil type.
The evaluation also illustrated that there can be large differences in yield and quality between cultivars depending on when and how often they are harvested. This is largely driven by optimum nutritional and water inputs. Forage sorghum has a high demand for nutrients and water in this environment and optimum yields will not be achieved unless these factors are met. Table 2 shows nutrient removal per tonne of biomass.
Two other critical points in relation to producing irrigated forage sorghum hay are:
1. The persistence of plant stands under continuous cutting. 2. Stem thickness, conditioning and dry down time.
Forage sorghum stands do not persist under continuous cutting in this environment. In general, by the end of the irrigation season (from April to early December) the plant numbers tend to be well below the optimum for viable yields. After one season of harvesting Sweet Jumbo the plant population had reduced to a non-viable level. Achieving a uniform plant stand of 800 000 to 1 200 000 plants/ha is required for viable production throughout the season. Plants die out because of the continual impact of machinery crushing and damaging 35 Pastoral the stems and growing points. Unlike Rhodes grass, forage sorghum ideally requires replanting each season.
Stem thickness determines how quickly hay will dry down to allow baling. This evaluation demonstrated that the thicker stemmed varieties (sorghum crosses) such as Sweet Jumbo, Betta Graze and Cow Pow took considerably longer to dry than the Sudan grass hybrid Superdan. Despite conditioning (pressing between rubber rollers on the mower/conditioner) the forages often took five to six days to dry sufficiently for baling. This is too long as it prevents the crop from being watered and reduces the effective growing period, number of harvests and potential yields. Selecting varieties with the thinnest stems, achieving high populations (to reduce stem thickness) and adequate mechanised conditioning is critical in irrigated forage sorghum production.
Figure 2. Irrigated forage sorghum yields from the 2004 evaluation at DDRF
Note: December harvest was an estimate made by several hand harvest samples. Due to large plot variability, each variety was assigned the same yield so as not to influence total machine harvest yields.
Irrigated lucerne 2004
In response to continual requests for information on lucerne (Medicago sativa) production, two varieties were sown in strips under the 10-ha centre pivot at DDRF in 2004. Approximately 1.5 hectares were sown in a non-replicated evaluation. Varieties Hunterfield and Faulkner were chosen because they persisted well at Katherine during the mid to late 1990s (M. Bennett, pers.com.). The objective in evaluating lucerne is to obtain some base line information on its production and develop recommendations on growing it in the Top End.
Several farmers have grown irrigated lucerne over the past 15 years in Katherine without much success. The major limitation to lucerne production in the Top End is that the plant is not well adapted to tropical conditions and therefore does not persist past the first wet season. Low yields and high production costs makes lucerne a risky proposition despite good local prices for good quality hay. If lucerne can be produced viably in the Top End by using improved agronomy and varieties, it would benefit the local stock feed industry and 36 Technical Annual Report 2004-05 provide a valuable rotation crop for irrigators. However, as with many products in the Top End, the local market is limited. Alternative markets would be needed for an industry to develop.
The varieties were planted on 6 April in a fine well-prepared seedbed. The seed was inoculated by using a slurry of inoculums, which was allowed to dry on the seed before planting. A small seed-box on a John Shearer Trash culti-drill was used to plant the seed at approximately 10 kg/ha. The seed was dropped on the soil surface and harrowed in using finger harrows. Pasture Generator® (14.0% P, 18% S 13.8% Ca) was applied prior to planting at 266 kg/ha providing 37kg P/ha, 47kg S/ha and 36 kg Ca/ha. Zinc and other trace elements had been applied previously and levels were deemed sufficient.
Treflan 400® (trifluralin at 400 g/L a.i.) was applied at the rate of 2.5 L/ha post-plant pre-emergent to control a range of summer grasses and broad-leaf weeds. The herbicide was incorporated with irrigation immediately after application. The crop was lightly watered (about 6 mm every two days) until establishment. Both varieties established well; however, some plants became infected with Rhizoctonia solani and several seedlings died as a result.
The early growth of the lucerne was slow and the disease (R. solani) accentuated the poor appearance. The crop suffered ill-thrift and nutrient deficiency. On 25 May, 66 kg/ha of urea (30 kg N), 2 kg/ha zinc heptahydrate and 1 kg/ha Solubor were applied to stimulate the crop. There was an apparent response as the crop improved in colour and vigour within five to 10 days.
The crop was harvested on 22 June and yielded 87 square bales averaging 21.2 kg. The overall average yield was approximately 1.2 t/ha for the area. There was no measurable difference in yield between the two varieties. The hay quality was moderate. Grass contamination reduced the purity of the hay. Analysis of the lucerne indicated 16 to 21.8% crude protein, 67.4% dry matter digestibility and 9.8 MJ/kg of dry matter.
Four additional harvests were undertaken resulting in an average yield of 1.7 t/ha/cut or a total of 8.5 t/ha for the season. This yield is considered low by southern standards; however, it was promising for a first year stand.
Spinnaker® (700 g/kg a.i. of imazethapyr.) was applied on 7 July at 100 g/ha to control weeds such as Bracharia sp., Digitaria sp., Ipomea sp., Sida acuta and caltrop (Tribulus terrestris). The application effectively suppressed the growth of most of the competing weeds. Spinnaker® was applied later in the season and Verdict® (520g/L a.i. of haloxyfop) was applied at the rate of 100 mL/ha plus Uptake® oil to control perennial grasses.
Weed control has been satisfactory and the stand has remained relatively clean. Perennial Sida and large caltrop are difficult to manage with herbicides and often require hand chipping. Nut grass (Cyperus rotundus) is present in the lucerne and is suppressed only with Spinnaker®.
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Figure 3. Lucerne hay yields from the first year irrigated stand at DDRF
Irrigated lucerne 2005
Both Faulkner and Hunterfield persisted through the 2004-05 wet season. The wet season was characterised by a number of extended (seven to 10 day) dry spells. Overall rainfall was approximately 250 mm less than the long-term average (1205 mm) at DDRF. The dry conditions particularly in February and March when only 60% of the long-term average rain fell, may have suited the lucerne.
The crop was sprayed on 12 January with 150 mL/ha of Verdict ® (520 g/L a.i.) plus 0.5 L/100 L of water of Uptake® spraying oil to control crows-foot grass (Elusine indica). The crop was “topped” on 1 February to reduce the rank growth and the biomass was removed. Due to the dry conditions the crop was irrigated on 17 February and received 12.5 mm of water. Rain fell on 21 February.
The first 2005 season harvest was undertaken on 4 April with subsequent harvests on 6 June and 8 July. Yields achieved to date are 3.12, 2.72 and 1.64 t/ha. The last harvest was round baled and the lucerne may have shed excessive leaf during the baling process.
New lucerne varieties
Promising results from the old lucerne varieties have led to the evaluation of two new varieties to determine if better quality and yields could be achieved. Two Pioneer varieties, L55 and L56, were sown on 7 April 2005. These are semi-winter dormant and are supposed to have superior persistence and disease resistance. They are reported to have thinner stems and to produce better hay than winter active varieties.
Pre-plant fertiliser included 300 kg/ha of muriate of potash (150 kg K/ha), 200 kg/ha of Trifos® (40 kg P/ha, 2 kg S/ha), 250 kg/ha and 400 kg/ha of gypsum and dolomite, respectively for sulphur and magnesium requirements. The area also received 10 kg/ha of zinc sulphate, 2 kg/ha of Solubor® and 1 kg/ha of copper sulphate to address trace element requirements.
38 Technical Annual Report 2004-05
Unfortunately, the first attempt to establish these plots resulted in a poor stand and severe nutgrass infestation. In an attempt to control the nutgrass, the area was sprayed with 9 L/ha of Roundup CT® (450 g/L a/i. glyphosate plus 250 mL/100L water of LI700® surfactant). This was unsuccessful so the area was let alone until the nutgrass recovered. The area was then sprayed with separate applications of 2, 4-D (2.0 L/ha of Amicide 625® plus Hasten® adjuvant) to control nutgrass and then Roundup CT at 5 0 L/ha to control emerging grasses. The 2, 4-D effectively suppressed the nutgrass. After a four-week plant-back period, the varieties were re-planted on 15 June and established successfully.
Seeding rate was approximately 41 kg/ha which is about twice the commercial recommendation. The seed was Gold Strike®, which has a pre-inoculation seed treatment. The treatment includes a fungicide, Rhizobium inoculant and a protective coating. Minimum germination was 85% and hard seed was 4% and 12%, respectively for L55 and L56. The use of high seeding rate was to ensure a uniform, dense stand and to allow the lucerne to compete with nut grass, which will eventually re-establish in the area. An area of 0.59 ha was established of each variety. After sowing, the area was sprayed with 3.0 L/ha TriflurX® (480g/L trifluralin) to control grasses and various broad-leaf weeds. The first harvest of these varieties was in August 2005.
Discussion:
Both Faulkner and Hunterfield persisted well through the 2004-05 wet season. Yields of 8.5 t/ha in the first season were moderate. At current cost of production and indicative prices for local quality horse hay, 6.0 t/ha is approximately the break-even yield. In the current season the lucerne has varied widely in production, ranging from a high of 3.1 t/ha in April to 1.6 t/ha in July. The causes need to be investigated. Temperature and moisture differences may have an effect.
One aspect for concern is the incidence of “little leaf” disease in the stand. The symptoms are similar to those of “witch’s broom” which occurs in lucerne-growing areas of NSW and Queensland. The disease is caused by a mycoplasma-like organism, which is transmitted by leafhoppers. The disease severely stunts plants and renders them unproductive. Significant numbers of plants affected by this disease and yields are likely to diminish if it continues to infect the stand.
Another production issue for quality lucerne in the Top End is to achieve the correct balance of stem and leaf moisture for baling. The problem arises when leaves dry within 12 to 18 hours but stems are too moist to bale. Sometimes lucerne is baled when too wet, resulting in spoilage. Older varieties have thicker stems and are harder to dry down evenly. The new varieties may help to overcome this problem.
PROJECT: Peanut Varieties for Northern Australia
Project Officers: P. Shotton, C. Ham, S. Lucas, C. Collins and F. O'Gara
Location: Douglas Daly Research Farm (DDRF)
Objective:
To evaluate and identify suitable peanut varieties for production in the NT.
Introduction:
This trial is a three year collaborative project between DPIFM, QDPI&F, the Grains Research and Development Corporation (GRDC) and the Peanut Company of Australia (PCA). Each year a number of new peanut lines are sown in replicated plots to evaluate yield, disease tolerance, kernel yield and the proportion of kernel and shell. The majority of this research is focused on identifying high yielding, disease resistant, high oleic oil varieties suitable for the NT. The market is demanding high oleic varieties due to their
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increased shelf life and health properties. The PCA is currently phasing out low oleic oil varieties and replacing them with varieties containing high levels of oleic oil.
Method:
Eleven varieties were evaluated in 2002, and 19 in 2003 and 2004. The varieties were hand-planted within a bulk peanut crop area under centre pivot irrigation at DDRF. The trials had a randomized block design with four replicates. Plots were 5 m long and two rows wide (row width was 0.9 m). Seeds were hand planted to achieve 120 000 established plants per hectare. Planting was in mid March and harvest time varied between varieties and seasons (late August to late September).
Approximately 6 ML/ha of water was used for the crop. Fertilisers were applied both pre- and post- emergent. Pre- and post-emergent herbicides were applied for weed control (Stomp and Basagran/Blazer mix). A fungicide spraying schedule of Electand Folicur was established for plant disease control.
Results:
The varieties were analysed as two separate groups: bunch and runner types (PCA predominantly runner type and QDPI&F bunch types). Because the two groups are usually graded differently and go to different markets, a direct comparison of the groups would be misleading.
The performance of each is rated on kernel yield per hectare and the proportion of different grades from each variety. Jumbo grades only and the combined grades of jumbo and grades 1 and 2 were analysed. Market preference affects total value as each grade varies in price.
Table 1. Mean yield and grading of each variety
PCA varieties t/ha Kernel (%) (%) (%) (%) (%) (%) (%) (%) (NIS) yield Jumbo G1 G2 Mfg Splits Oil ts Oil hp Shell t/ha Fadden 7.9 6.3 48.6 6.1 5.7 0.4 14.7 2.3 1.9 20.3 Menzies 6.8 5.6 51.7 7.2 4.6 0.6 12.5 2.7 2.4 18.3 Chifley 8.1 6.7 51.4 8.0 3.8 0.5 11.7 2.3 5.5 16.9 Lyons 6.4 5.3 47.5 10.1 8.0 0.9 10.5 3.6 2.3 17.1 Forde 6.8 5.4 52.3 7.5 4.8 0.3 9.4 1.7 3.1 20.8 McMahon 7.1 5.7 49.4 5.6 3.6 0.3 16.4 1.6 2.9 20.3 Deakin 7.6 6.2 47.1 5.6 6.6 0.7 14.3 3.4 3.8 18.6 SO95 6.7 5.5 47.0 5.0 3.0 0.4 19.4 2.3 4.5 18.3 Holt 7.3 5.9 56.5 5.0 2.9 0.2 10.3 2.2 4.1 18.8 QDPI&F varieties D107-5-p5-2 7.6 5.5 16.2 24.0 9.5 1.1 20.1 0.9 0.0 28.1 Middleton 7.7 5.7 23.2 17.0 10.8 3.0 18.2 2.1 0.0 25.8 D117-6-p4-1 7.3 5.4 13.4 19.1 10.6 1.4 27.3 1.3 0.0 26.9 D117-1-p1-4 7.3 5.2 30.1 19.2 7.9 1.0 12.2 0.9 0.0 28.8 NC 7 7.2 5.1 26.7 16.7 8.4 1.3 16.3 1.0 0.0 29.6 Streeton 6.8 5.0 13.1 27.8 17.9 2.2 11.3 1.3 0.0 26.3 Wheeler 7.6 5.7 26.8 22.0 7.0 1.1 16.7 1.0 0.0 25.3 D57-1-p2-10 7.2 5.4 7.5 24.5 25.0 2.9 14.0 1.2 0.0 24.9 D48-4-p4-3 7.1 5.0 23.7 16.2 8.4 1.3 19.9 1.5 0.0 28.9 Conder 7.4 5.3 18.6 23.5 10.9 1.2 16.8 0.9 0.0 28.1
Within the PCA varieties Chifley had a significantly high kernel yield per hectare. However, no significant differences were found in the QDPIF varieties.
40 Technical Annual Report 2004-05
8.0
7.5
7.0
6.5
6.0
5.5 Kernel yield in t/ha in yield Kernel
5.0
4.5
4.0 Fadden Menzies Chifley Lyons Forde McMahon Deakin SO95 Holt Treatment
Figure 1. Weighted means (0.99 confidence limits) using PCA kernel yield as a predictor
Table 2. Tukey’s HSD test to identify significantly different groups, based on kernel yield (t/ha)
Variety Kernel yield (t/ha) Grouping Chifley 6.74 a Fadden 6.28 ab Deakin 6.16 ab Holt 5.90 ab McMahon 5.67 b Menzies 5.59 b SO95R 5.46 b Forde 5.42 b Lyons 5.27 b Note: Varieties with different letters are significantly different
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6.4
6.2
6.0
5.8
5.6
5.4
5.2
5.0 Kernel yield int/ha yield Kernel 4.8
4.6
4.4
4.2 D107-5-p5-2 D117-6-p4-1 NC 7 Wheeler D48-4-p4-3 Middleton D117-1-p1-4 Streeton D57-1-p2-10 Conder Treatme nt
Figure 2. Weighted means (0.95 confidence limits) using QDPIF kernel yield as a predictor found there were no significant differences between the varieties
Diseases
Peter Trevorrow (QDPI&F) assessed disease incidence and severity 38 days prior to harvest. Due to the low incidence of disease in the trial no statistical analysis was undertaken. Table 3 shows the ratings of diseases found.
Table 3. Disease ratings
Variety Leaf spot* Soil borne disease** Menzies 1.2 0.4 D57-1-2-10 1 0.8 Middleton 1 0.6 Fadden 1 0 D107-5-5-2 1 0 Forde 1 0.2 Chifley 1 0.4 SO92R 1 1 McMahon 1 0.2 Conder 1 0.2 Hughes 1 0 Deakin 1.2 0 D48-4-4-3 1 0.2 D117-1-1-4 1 0.2 Lyons 1 0.6 Wheeler 1 0.4 Streeton 1 0.4 NC7 1 0.2 D117-6-4-1 1 0.2 * Leaf-spot rating: 1= No disease, 2 = Very few lesions in lower canopy, 3 = Few lesions in lower and upper canopy, 4 = Some lesions with slight defoliation, 5 = Lesions noticeable in upper canopy with some defoliation, 6 = Lesions numerous with significant defoliation, 7 = Lesions numerous with heavy defoliation, 8 = Very numerous lesions on few remaining leaves with very heavy defoliation, 9 = Very few remaining leaves, 10 = Plants dead. **Soil borne disease rating: This rating reflects the average number of plants affected by a soil borne disease in the experiment.
42 Technical Annual Report 2004-05
Discussion:
This was the final year of a three-year trial. In year one issues such as plant populations, wallaby and brolga damage affected the trial. In year two strategies were put in place to deal with these issues. Drying racks were constructed to dry the harvested varieties and prevent access to wallabies. Maize strips were planted at intervals throughout the trial to form a visual barrier and inhibit the movement of brolgas into the crop. This worked well and damage by brolgas was restricted to the outer extremity of the bulk area, leaving the trial area relatively unaffected.
The trials have been managed using "best practice" which has included recommended fertiliser, watering and disease and insect control measures. Table 1 indicates that all varieties performed well in terms of total pod yield. Overall, the trial went well with all objectives achieved.
PCA varieties
Chifley was the highest-yielding variety, had a low shell percentage but did not vary significantly from Fadden, Deakin or Holt in kernel yield. Chifley gave a significant higher yield than the remaining five PCA varieties. None of the other varieties differed significantly in total kernel weight. When the percentage of jumbo kernel was analysed, Holt was significantly higher than some varieties but did not differ significantly from Ford, Menzies or Chifley. Holt achieved a high percentage of jumbos and combined grades and had a total kernel yield of 7.27 t/ha.
When the combined percentages of jumbos and grades 1 and 2 were analysed Lyons achieved the highest; however, it preformed lower in total kernel yield and jumbo percentage. SO95R was the poorest performer with low kennel yield, low percentage of jumbos, grades 1 and 2 and had a high percent of splits (19.4%).
There was variation within the weighted means on kernel yield particularly in the varieties Lyons and Deakin. This was probably due to Lyons having a lower yield in rep 5 due to weed competition (nut grass) and Deakin having a higher yielding plot in rep 1 of 7.27 kg/ha.
QDPI&F varieties
There were no significant differences based on total kernel yield per hectare (Table 1). However, there were significant differences when assessing the percentages of jumbo kernels and the combined grades of jumbos, grade 1 and grade 2.
When comparing the percentages of jumbos the varieties fell into two main groups. D117-1-1-4, Wheeler, NC7, D48-4-p4-3 and Middleton were higher than D571-2-10, Streeton, D117-6-4-1, D107-5-5-2 and Conder. Although Streeton had a low jumbo percentage, it was highest with the combined grades of jumbos and grades 1 and 2. The lowest performers of the trial were D117-6-4-1 having low grades of jumbos, grades 1and 2.
The poorest performing QDPIF variety was D57-p2-10 having the lowest percentage combined grades of jumbos, grades 1 and 2 and had a high percentage of splits (27.3%) although did not differ significantly from other varieties in total yield.
43 Pastoral
Sub-program: Cotton
PROJECT: Management System for Diseases of Cotton in the Katherine Region
Project Officers: S. Bhuiyan, M. Boyd and C. Martin
Location: Katherine
Objectives:
To determine the effect of foliar application of potassium on development of alternaria leaf spot of cotton
To determine the effect of chemical fungicides on development of alternaria leaf spot of cotton
Background:
Although alternaria leaf spot is considered to be a minor disease of cotton (Gossypium hirsutum) in southern Australia, it appears to be of major importance in northern Australia. It has been a major problem of cotton in the Katherine (NT) and Kununurra (WA) regions for several years. There are reports of high disease incidence in the Burdekin region of Queensland. Both Alternaria macrospora and A. alternata are implicated as the causal organism of the disease. In Zimbabwe, it was reported that potassium (K) deficiency during growth and flowering predisposed cotton plants to alternaria leaf spot. It is believed that cotton plants become deficient in K during flowering and boll formation. Foliar application of K at flowering and afterwards may reduce the K deficiency level as well as alternaria leaf spot on cotton. Chemical fungicides are being used elsewhere to control various leaf diseases.
Method and Results:
Effects of foliar K
An experiment was undertaken at the Katherine Research Station on three randomly selected replicated plots (9 m x 50 m each). KNO3 was applied at the rate of 13 kg/ha with the help of a boom sprayer. The first application was conducted approximately seven days before flowering and the following three applications after flowering at two weeks interval. Three unsprayed plots were used as controls.
Ten randomly selected plants from each replicate were marked with spray paint. The plant next to the painted plant was selected for assessment of disease incidence and severity. Main stem leaves at three canopy levels (1-7 nodes, 8-14 nodes, and 15+ nodes) were assessed visually for disease incidence and severity. A modified visual scale was used for the assessment of severity of alternaria leaf spot. Assessments were conducted weekly between July and September, 2004.
Disease incidence
There were no significant differences in disease incidence between sprayed and unsprayed plots (data not presented). Most of the leaves became infected with alternaria two to three weeks after the first assessment.
Disease severity
Disease severity was higher at the middle canopy level (8-14 nodes) in both sprayed and unsprayed plots (Figure 1). Significant differences in severity between sprayed to unsprayed middle canopy levels were
44 Technical Annual Report 2004-05 observed from late July to the third week of August. There were no significant differences in disease severity between sprayed and unsprayed plots at the 1-7 or 15+ nodes canopy level.
Heavy overnight dew on middle canopy leaves and associated cooler night temperature in June, July and August may have predisposed middle leaves to leaf spot disease. Due to continuous development of new leaves on 15+ nodes canopy levels, the overall severity of disease on top leaves was less. Likewise, lower canopy leaves had relatively less exposure to heavy dew, thus disease severity was less.
Sprayed/Bottom 20.00 Unsprayed/Bottom Sprayed/Middle Unsprayed/Middle Sprayed/Top 15.00 Unsprayed/Top
10.00 M ean Incid
5.00
0.00 2-Jul 12-Jul 22-Jul 1-Aug 11-Aug 21-Aug 31-Aug 10-Sep 20-Sep 30-Sep
Figure 1. Severity of alternaria leaf spot over time at various canopy levels after spraying with foliar K
Leaf shedding
Leaf shedding was higher in the middle canopy level (8-15 nodes) in both sprayed and unsprayed plots (Figure 2). Significant differences in leaf shedding were observed between sprayed and unsprayed plants in the middle canopy level from the last week of July to the third week of August. There were no significant differences in leaf shedding severity between sprayed and unsprayed plots at 1-7 or 15+ nodes canopy level.
8
Sprayed/Bottom 7 U nsprayed/Bottom Sprayed/Middle 6 Unsprayed/Middle Sprayed/Top 5 U nsprayed/Top
4
3
Num ber of Le Num of ber 2
1
0 2-Jul 12-Jul 22-Jul 1-Aug 11-Aug 21-Aug 31-Aug 10-Sep 20-Sep 30-Sep
Figure 2. Shedding of leaves over time due to alternaria leaf spot at various canopy levels after spraying with foliar K
45 Pastoral
Fungicide trial
Three fungicides from two groups were used:
- Dithane Rainshield 750 (Mancozeb) - Score 250EC (Difenoconazole) - Folicur 430SC (Tebuconazole)
Spray applications were conducted as follows
- Dithane (2 kg/ha) + Score (500 mL/ha) - Folicur (250 mL/ha) + Agridex (1 L/ha)
• Dithane (2 kg/ha) + Score (500 mL/ha)
- Three spray applications (May 7 to May 31) - Two-week intervals
• Folicur (250 mL/ha) + Agridex (1 L/ha)
- Six application (June 15 to Aug 20) - Two-week intervals
No significant differences were observed between sprayed and unsprayed plots in alternaria leaf spot disease incidence (Figure 3).
120
100
80
Sprayed 60 Unsprayed Incidence
40
20
0
4 4 4 04 04 04 04 004 004 /20 /20 /20 2 /2 9/ /0 /09 1/07/20 8/07/200 4/08/200 1/08/200 8/08 5/08 1/09 8 5 07/07/2004 14/07/2004 2 2 0 1 1 2 0 0 1 Date
Figure 3. Effects of fungicides application on incidence of alternaria leaf spot in cotton at Katherine Research Station, 2004
46 Technical Annual Report 2004-05
Significant differences in leaf spot disease severity were found between sprayed and unsprayed plots (Figure 4) during the whole trial period.
18
16
14
12
10 Sprayed Unsprayed
Severity 8
6
4
2
0
4 4 4 04 04 04 04 004 004 /20 /20 /20 2 /2 9/ /0 /09 1/07/20 8/07/200 4/08/200 1/08/200 8/08 5/08 1/09 8 5 07/07/2004 14/07/2004 2 2 0 1 1 2 0 0 1 Date
Figure 4. Effects of fungicide application on severity of alternaria leaf spot in cotton at Katherine Research Station, 2004
Acknowledgement
Financial assistance was provided by the Cotton CRC.
47 Pastoral
Program: Dry Land Cropping
Sub-program: Farming Systems
PROJECT: Sesame Industry Development
Project Officers: M. Bennett, D. Owens and G. Routley
Location: Katherine Research Station
Objective:
To identify and develop new sesame genotypes suitable for northern New South Wales, central Queensland and northern Australia.
Background:
As a result of the release of sesame cultivar Edith, potential yields of high quality seed have been increased by 10%. However, Edith does not have capsule characteristics that minimise seed loss as the crop matures and capsules dehisce. A breeding program was established to transfer the strong seed attachment from Hnani 25/160 to Edith in 1993. Five lines were identified in 1997 as having strong seed attachment. A further five lines were identified in 1998. These lines presented a range of phenotypes, early, mid and late maturing, suitable for northern NSW, central Qld and northern Australia, respectively. Self-pollinated seed of each line was produced, planted and the best individual plants were identified. Commencing in 1997-98, experiments were conducted to identify and develop new superior sesame cultivars for the sesame growing regions of Australia. These externally-funded experiments were completed in 2003-04. Plant Breeders’ Rights for cultivars, Rakabe and Rosemarie, were obtained in June 2005. National and international interest in the remaining experimental lines as potential parents for a breeding program to develop a “sweet “ cultivar with export potential to Japan resulted in preliminary screening of the lines in 2004-05.
Method:
This wet season a replicated experiment evaluated the remaining 20 selections for suitability to mechanized agriculture, while the seed harvested from these plots was sent to two Japanese companies for roasting and flavour assessment. An additional area was sown with three internationally-recognized sweet cultivars, Taihaku White (Japanese origin), Sudan White (Sudanese origin) and Paraguay Escoba (Paraguayan origin) plus the commercial Australian cultivars, Edith, Yori, Giles Rakabe and Rosemarie. The sweetness of the international cultivars provided a benchmark on which to score the experimental selections and the Australian cultivars.
Progress report
Results for sesame flavour assessments indicate that Sudan and Giles scored a 4 (5 being the best), Paraguay, Taihaku and two experimental lines scored a 3. The remaining lines were not acceptable to the Japanese market. Suitability to mechanised agriculture in Australia was scored on a 50-point scale; Sudan scored the lowest, 5 while Paraguay and Taihaku scored 8, Giles 23. The best experimental line scored 39. All parties recognised that the international lines could not be grown commercially in Australia. The parties were interested in a commercial relationship for growing or buying Giles sesame grain. Discussions to this effect will proceed later in the year. The Japanese have suggested that four Ethiopian and some Chinese lines should be investigated before the sesame breeding program is closed.
48 Technical Annual Report 2004-05
Program: Buffalo Production
PROJECT: TenderBuff Development and Supply Project
Project Officers: B. Lemcke, E. Cox, L. Huth and BHF Staff
Location: Beatrice Hill Farm (BHF)
Objectives:
To supply, promote and implement the TenderBuff Quality Assurance program for local and interstate markets.
To ensure year-round supply of TenderBuff in the Northern Territory.
Background:
The TenderBuff program was initially started to provide higher returns to the producer whose buffalo numbers were small, post - BTEC. It was seen as an appropriate substitute for the feral fillet market to restaurants using a much larger range of cuts. The Agriculture Branch runs the project in conjunction with the NT Buffalo Industry Council and provides the personnel to do quality assurance and branding of carcasses at the abattoir. The price paid to the producer remains at $3.10 per kg hot standard carcass weight (HSCW). There are five specifications that a carcass must comply with to receive the TenderBuff strip brand (see below).
Animals are now sourced mainly from commercial properties and raised at BHF to maintain a steady year- round supply. With its extensive floodplain and ponded pastures, BHF is able to fatten stock all year round and is only a 45-minute drive from the Litchfield abattoir. Several producers are now gearing up with suitable pastures to turnoff animals directly to the market
Since March 2001, BHF has concentrated on producing TenderBuff, while sending only non-conforming stock to the Brunei market for the supermarket trade.
TenderBuff has lower cholesterol and fat than beef, two factors which can be used for positive marketing of the product. Some ¾ River crosses are showing increased fatness on the rump and ribs; however there does not appear to be any increase in intramuscular fat. As River cross buffalo grow much faster than Swamp progeny, they can be turned off much earlier, resulting in much more tender meat.
Method:
The current specifications are:
1. 150-300 kg HSCW. 2. 3-12 mm fat at p8 site. 3. No permanent teeth. 4. Electrically stimulated carcass. 5. Muscle pH below 5.8 after 18 hours.
Agriculture Branch staff monitor TenderBuff animals through the abattoir on slaughter day and carry out chiller assessment the following day.
The discount grid determines the sale price to the wholesaler of animals that do not meet the five specifications. This usually amounts to a 10% discount for each non-conformance to specifications.
49 Pastoral
We are continuing to castrate all purchased and BHF-grown bulls that are not suitable for sale as breeders. This reduces unwanted pregnancies in females used for TenderBuff. The only other management option would be to use the Willis spay technique on females. The problem of less than 3 mm of fat in bulls in the dry season appears to have been overcome by castration as steers carry more fat, although less than that in heifers.
Our policy is to purchase animals that require putting on at least 100 kg of live-weight gain prior to turnoff. The preferred weight and fat range at turnoff is in excess of 400 kg LW with more than 5 mm of P8 fat.
Results:
Table 1. Carcass parameters for TenderBuff
July-December January-June July-December January-June 2003 2004 2004 2005 No of animals 40 36 51 47 Mean HSCW (kg) 230.3 241.1 217.3 231.6 Mean eye muscle area (cm2) 59.5 63.0 58.6 61.4 Mean pH 5.56 5.49 5.53 5.50 Mean carcass length (cm) 104.8 106.1 103.9 105 Mean gross ($) 685.90 741.33 656.67 711.32 Mean grid ($/kg) 2.98 3.07 3.02 3.07 Mean p8 fat (mm) 7.6 8.4 7.5 9.1 Mean dressing (%) 51.9 50.8 50.9 51.4 Total carcass wt (kg) 9211 8681 11085 10886 % River cross 11/40=27.5% 13/36=36.1% 33/51=64.7% 32/47=68.1%
This year there was an increase (29% vs. 11%) in demand and consumption of TenderBuff animals over last year. This, with a slight decrease in average carcass weight, resulted in a 23% increase in the amount of TenderBuff sold. The slight drop in average eye muscle area probably reflects the slightly lower average dressed weights. This could probably go down even further in the future to around 200 kg dressed weight, which would lower the fat thickness. The earlier turnoff age would give benefits in increased tenderness of the meat and therefore eating quality. The upward trend in consumption has mainly been due to extra interstate purchases of vacuum-packed primal cuts (as whole carcasses) from the local Darwin wholesaler. The other noticeable trend is the large increase in the proportion of River-cross buffalos being processed, which is due to their better growth rates.
Table 2. Comparison between Swamp and River crossbreds during July 2004 to June 2005
Swamp River crosses % Difference over Swamp No of animals 33 65 Mean HSCW (kg) 216.3 228.2 +5.5% Eye muscle area (cm2) 55.1 62.4 +13.24% Mean pH 5.51 5.52 +0.1% Mean carcass length (cm) 104.1 104.6 +0.4% Mean grid ($/kg) 3.05 3.04 -0.4% Mean p8 fat (mm) 6.2 9.4 +51.6% Mean dressing (%) 50.36 51.54 +2.3 Mean price per head ($) 660.63 694.18 +5.1%
50 Technical Annual Report 2004-05
This is the first year that River-cross carcasses have out-numbered Swamp carcasses. The expected differences are again evident in all the production traits with the exception of the extra fat being a slight disadvantage. This is negated by turning off earlier, at a lighter weight, and presumably the meat would be more tender. The differences between pH, length and grid price averages are minor, except that the length to live-weight ratio is probably slightly higher in the Swamp carcasses. This however does not mean better meat yields. The better dressing percentage is quite significant and means extra income to the producer. This is also reflected in the eye muscle differences which favour the crosses significantly.
PROJECT: Riverine Buffalo and Crossbreeding Project
Project Officers: B. Lemcke, E. Cox, G. Jayawardhana and BHF Staff
Location: Beatrice Hill Farm (BHF)
Objectives:
To determine the merits of crossbreeding and upgrading to Riverine buffalo for the NT buffalo industry.
To distribute suitable progeny from the program to industry for breeding or for supply of TenderBuff.
To demonstrate sustainable buffalo production systems.
Background:
It was the long held dream of pioneer buffalo researcher, the late Don Tulloch, and the vision of the NTBIC to introduce Riverine blood into the Australian swamp buffalo population. The dream became reality in 1994 with the importation of two bulls, followed over the next three years by a further four heifers and two more bulls. Two of these heifers were purchased by a private producer and left at BHF for mating. A crossbreeding program started and progeny performance is monitored. Progeny are also sent to supply TenderBuff. The purebred group has increased now to 47 animals at BHF, which is less than during last year due to a number of sales. Two of the original imported bulls died; one accidentally whilst on loan to a local producer and the other as a result of TB de-stocking, seven years ago.
The aim of the project is to produce purebred Riverine buffalo from both directions, by using the purebred cows to increase their numbers from within and also by crossbreeding then backcrossing to purebred through ¾, 7/8 and 15/16 generations back to purebred Riverine.
It is expected that during this process we will be able to identify all those mixtures of the two breeds that will best suit the various meat, export and dairy produce markets in Australia and overseas.
A co-operative arrangement exists with the Australian Dairy Buffalo Co in Millaa Millaa Qld to supply data on the milk-producing potential of the various crosses compared with the pure Riverine.
A small number of heifers which were sold to a dairy farmer in Maleny Qld in 2004 have started calving. Another four purebred heifers have been purchased for delivery later in 2005.
Method:
All stock is held at Beatrice Hill Farm. Half-bred cows and heifers are mated to the imported bull “OJ” to produce ¾ calves. Bull 5775 was the sire of all the 7/8 calf group. Some semen of Italian milking buffalo has also been imported. Semen from three bulls has been used in AI projects. Some of the purebred cows and 7/8 heifers have been inseminated with Italian semen and “Bill’s” semen. A half-Italian bull (by AI) No.5796 has been used to sire this year’s F1 calves. It was mated with swamp females this wet. “Bill”, had been 51 Pastoral exposed to TB-infected cows and was subsequently put down. Before that, it was trained to an artificial vagina and about 1200 straws of semen were collected from it and frozen in liquid nitrogen for later use.
Results:
Table 1. The composition of Riverine and crossbred buffalo groups at BHF, June 2005
Imported Local Breeder Yearling Yearling Male Female Total bulls bulls cows bulls heifers calves calves
Purebred 2 3 25 4 5 6 2 47* Riverine Swamp - 34 1 35 F1 - 36 6 9 6 57 3/4 33 8 9 11 61 7/8 6 18 8 12 15 9 68 15/16 1 2 1 2 1 7 Total 2 10 146 14 32 41 30 275 * The lower number of purebred Riverine this year is due in part to the sale of 10 young bulls.
Table 2. Calving and pregnancy results for 2004-05
Breeder group Calves born/cows No. pregnant Pregnancy rate No. pregnant + wet mated = Calving June (%) cows/total wet cows rate 2004-05 2005/cows % wet cows calves mated 12-2004 pregnant Swamp cows 15 / 31= 48% 15 / 33 45 5/17 = 29% F1 cows 15 / 28 = 54% 26 / 35 74 12/21 = 57% ¾ cows 20 / 36 = 56% 28 / 34 82 16/21 = 76% 7/8 cows 3 / 4=75% From AI 14/18 78 1/2 = 50% Riverine cows 15/15 = 100% 18/25 From AI 72 10/15 = 67% (3 rounds)
Pregnancies this year show an increase over last year, except in the Swamp group due to low pregnancy rates in wet cows and six of eight heifers that were empty. There was also some evidence of bullying by some of the older cows in the group.
This was the first year with a significant turn-off of purebred progeny and the sale of some purebreds to new owners (five females).
The buffalo program of RIRDC is funding a project that has three components. First, a synchronisation protocol needs to be developed to deliver good AI outcomes. The second is to set up a database for the entire Australian buffalo industry. The third is to analyse and report on the genetics of the swamp buffalo from historical data held by DPIFM. The results from the purebred Riverine AI group of 25 cows included18 pregnant after three rounds, including nine heifers. Empty cows were sent to the bull (four out of seven were heifers which had difficulties with uterine insemination).
52 Technical Annual Report 2004-05
Program: Agroforestry
PROJECT: Agroforestry
Project Officers: D. Reilly, B. Robertson, K. Neitzel and M. Clark
Location: Four sub-regions of the Top End: the lower Mary River, Katherine, the Daly region and the Darwin rural area on private properties.
Objective:
To provide research and development, extension, education and training in agroforestry.
Introduction:
The Top End Regional Tropical Hardwood Forestry project, which is funded by the Natural Heritage Trust, has completed a three year planting program. The project began in 1998 with the establishment of eight trial sites in the four identified sub-regions of the Top End. This followed in the next two years with the planting of another 16 sites, bringing the total number to 24 sites across the Top End of the Northern Territory. Each trial site is between 1 and 2 hectares.
Method:
The aim of the project was to encourage farm forestry on cleared agricultural land in the Top End region to promote the production of wood and non-wood products and to integrate it with other farming activities. The preliminary trials have now been established on 24 x 1-2 hectare sites and have been measured and assessed for growth and performance across the four main agricultural sub-regions of the Top End.
Suitable species and provenances of trees for planting on to private properties were chosen by a steering committee with an appropriate mix of exotic and native hardwoods. The main selection criterion for the choice of species was high value hardwood. It did not matter whether trees were native or introduced. An effort was made to include as many native species as possible without compromising the objective of the project, which was to “incorporate the growing of high value hardwood timbers on already cleared agricultural land”.
In the first year, 12 species were selected for the research trials and /or demonstration plots across all the sites selected. They were African mahogany (Khaya senegalensis), two species of American mahogany (Swietenia humilis and S. macrophylla), Rosewoods (Pterocarpus spp.), West Indian cedar (Cedrela odorata), teak (Tectona grandis), talisan (Terminalia belerica), Indian mahogany (Chukrasia velutina) and of the Australian natives, red mahogany (Eucalyptus pellita), red cedar (Toona ciliata and black bean (Castanospermum australe. Over the next two years of planting, these were the core species for evaluation. Others were included to suit soil types and land owner wishes. Other tree species planted in subsequent years included cypress pine, Leichardt pine, paperbarks, ironwood, bush apple and the Central American tree species, Enterolobium cyclocarpum.
All trials were randomised complete blocks. On each site six species were planted, each represented by 7 x 7 plant plots in four replications (196 plants per species). Landowners prepared the sites, fenced them and maintained them, including weeding. In most cases the seedlings were planted into already cultivated lines (not always possible) at a spacing of 3 m between rows and 3 m along rows resulting in 1111 stems/ha.
Most seedlings were raised in either “Plantek Side Slot Trays” or “Hiko” 40 cell trays using a potting mix of sand, coco peat, perlite and osmocote. Seed was sown in August/September and trays were placed in
53 Pastoral shade houses. Seedlings for some species were sourced from the Howard Springs Forest Reserve where re-generation from earlier evaluations yielded large numbers of seedlings. They were pulled from the ground and propagated in small pots or planted directly into the new trial areas. African mahogany, rosewood, Indian mahogany and Terminalia belerica were sourced as striplings in this manner.
Results:
Overall the best performing species in 2004 was African mahogany which performed best across all sites. This result is highlighted further when all parameters for economic performance are considered, including survival. The most impressive aspect of the growth of African mahogany is the consistent increase in trunk diameter. An average of nearly 12 cm growth was achieved on some sites such as Parker’s and Walsh’s in Katherine, which is far greater than the 2 cm diameter increase per year expected on good sites for the species else where. Data was collected in June and July 2002 where trees were measured for height and, where appropriate, trunks were measured for diameter at breast height (DBH) of 1.3 m. The most recent assessment was undertaken in mid 2004. During this assessment, not all of the 24 sites were measured as very little new information could be gained from most sites that were measured only two years ago. The major interest prompting assessment at this time was to up-date the information on African mahogany which was a component in many sites and was /is the best performing species in those sites. A number of parameters in addition to those used previously were added during the 2004 assessment and included bole length, straightness score and the number of forks above and below DBH which will give us an indication of the form of the trees as well as their growth performance. Figure 1shows the performance of some of the species in a number of sites and their rate of survival at those sites.
Mean annual height increment (m) MAI
2.0 K.senegalensis T.grandis S.humilis 1.8 c. odorata T.belerica S. macrophylla 1.6
1.4
1.2
1.0 (m)
0.8
0.6
0.4
0.2
0.0
) ) y ey rt rker nd han inski ick he e Pa H yla Walsh Kalano dr Do Me Dum FredsPass rg( erg(irrigated e b nTilb a VanTil V Sites
Figure 1. The incremental growth in height per year for all species across all sites
The effect of sites on tree growth is becoming quite obvious after nearly five years since planting. They indicate that in the NT environment the trees need relatively fertile and well-drained soils for the production 54 Technical Annual Report 2004-05 of high value hardwoods. The “Duminski site had heavy compacted soils that became quite water-logged during the wet season.
The range of species planted over the three years of the trials was diverse. The range of species used in this study was reduced to those that were common to most sites in the first two years of the establishment of the trial. The persistent species were Khaya senegalensis, Tectona grandis, Terminalia belerica, Swietenia humilis, S. macrophylla and Cedrela odorata of which K. senegalensis performed best over the two years of establishment. On some sites that were judged to be in poor condition in 2002, it was decided to measure only K. senegalensis so that there was data for at least one species across the maximum number of sites planted in the first two years of the trials. K. senegalensis was the only species measured at Duminski, Kalano and Hickey. Duminski and Kalano had the poorest performance overall, although Kalano ranked high for bole increment.
The sites where K. senegalensis appeared to fail were classified as ‘poor’. This was the case in Duminski (established 1998-99) and Kalano (established 1999-00) properties. The compacted Podzolic soils at Duminski (without irrigation) have indicated poor growth, while the traditionally-owned site at Kalano near Katherine on Tippera soil where maintenance has been minimal and which experienced a fire in 2002, results in 2004 were poor.
The sites in Katherine on Tippera soils - Parker, Meehan, Kalano and Hickey - and on river levee soils, such as Walsh, consistently ranked in the top groups (Table 1) for all traits across all species. The notable exception was at Fred’s Pass where K. senegalensis growth in height was affected by browsing possums.
Overall, the best site ranking first or second for bole and straightness traits in most species in the assessment was Walsh on river levee soils in the Katherine region. However, on a similar soil type site, Van Tilburg near Adelaide River (planted in 1999-00), the ranking for traits across species was generally low, especially for T. grandis and K. senegalensis.
In the main species assessed (Figure 1) the three that performed best were K. senegalensis, T. grandis and S. humilis. They had fairly similar growth at most sites. Meehan appears best (mostly) or equal to the other sites for survival and growth. This was also the case for form characteristics of bole and stem straightness, at the Meehan site where it was surpassed for bole length only by Doherty, and for straightness only by Walsh. These results suggest the superiority of soil type at the Meehan site for best tree growth compared with the other soil types. The better growth at this site (even when compared with other sites with a similar soil type) can be partially explained by the special care given by the landholder. Additional applications of fertiliser to the site (often left-over after fertilising his mango block) may also explain the superior performance at this site. The better results for Doherty (bole) and Walsh (straightness score) compared with Meehan cannot be explained.
Previous reports have shown that other species were growing well across some sites and were performing as well as the African mahogany in terms of growth. They were Eucalyptus pellita and Swietenia spp, but they have slowed down in growth and are becoming increasingly prone to termite attack. This aspect demonstrates the benefit of allowing at least one third of a tree’s rotation time to be reached prior to making judgement on its suitability to certain sites.
In addition to the species discussed, other species which were not part of this study have performed well, such as Chukrasia velutina, C. tabularis, Pterocarpus macrocarpus and P. indicus. C. velutina was planted on a number of sites, but appeared to be performing best at Meehan.
All the four replicates at that site grew well with very good form and straightness. The mean height was 8.16 m and the mean DBH was 11.58 cm. This compares very well with K. senegalensis on the same site with a mean height of 8.3 m and a mean DBH of 11.1 cm.
55 Pastoral
Table 1. Species comparison across sites for measured traits (groups within columns with the same letter are not significantly different) Species Survival Group Height (MAI) Group DBH (MAI) Group Bole (MAI) Group C.odorata Fred’s Pass a Walsh a Walsh a Walsh a Parker a Parker b Parker a Parker a Van Tilberg Van Tilberg (irrigated) a b,c Van Tilberg (irrigated) b Van Tilberg (irrigated) a (irrigated) Walsh a Fred’s Pass c Fred’s Pass b Fred’s Pass a K.senegalensis Van Tilberg (irrigated) a Meehan a Hickey a Meehan a Walsh a Walsh a,b Meehan b Kalano a,b Parker a Doherty b,c Van Tilberg (dry land) b,c Doherty b Doherty a,b Van Tilberg (dry land) b,c Doherty b,c Van Tilberg (irrigated) b,c Van Tilberg Meehan a,b b,c Van Tilberg (irrigated) b,c,d Parker c,d (irrigated) Van Tilberg (dry land) a,b Hickey b,c Fred’s Pass c,d Hickey c,d,e Duminski a,b Parker c Parker d Van Tilberg (dry land) c,d,e Fred’s Pass a,b Kalano d Walsh d Walsh c,d,e Hickey b Fred’s Pass e Kalano e Duminski d,e Kalano b Duminski f Duminski f Fred’s Pass e S.humilis Walsh a Meehan a Walsh a Meehan a Meehan a Parker a,b Fred’s Pass a Van Tilberg (irrigated) a,b Van Tilberg (irrigated) a Walsh a,b Parker a Van Tilberg (dry land) b,c Fred’s Pass a Fred’s Pass b,c Meehan a Doherty c Van Tilberg Doherty a c,d Van Tilberg (dry land) b Walsh c,d (irrigated) Parker a Doherty c,d Van Tilberg (irrigated) b Parker d Van Tilberg (dry land) a Van Tilberg (dry land) d Doherty b Fred’s Pass d S.macrophylla Meehan a Meehan a Meehan a Meehan a Parker a Parker b Walsh b Parker b Walsh a Walsh b Parker b Walsh b T.belerica Parker a Parker a Parker a Parker a Fred’s Pass a Fred’s Pass b Fred’s Pass b Fred’s Pass b Walsh a Walsh b Walsh b Walsh b T.grandis Meehan a Walsh a Fred’s Pass aWalsh a Van Tilberg (irrigated) a,b Fred’s Pass a Walsh a Parker b Doherty a,b Meehan a Parker a Fred’s Pass b,c Parker a,b,c Parker a Meehan a Van Tilberg (irrigated) b Van Tilberg Walsh b,c b Van Tilberg (irrigated) b Meehan b (irrigated) Fred’s Pass c Doherty c Doherty b Doherty c 56 Technical Annual Report 2004-05
P. macrocarpus and P. indicus were planted as demonstration species at both Parker and Walsh where DBH was measured on the net plot of 25 trees and height was scored as predominant. At Parker, P. macrocarpus had a mean height of 8.4 m and mean DBH of 10.72 cm, and P. indicus had a mean height of 11.46 m and mean DBH of 12.5 cm. At Walsh, P. macrocarpus had a mean height of 12.87 m and mean DBH of 13.53 cm, and P. indicus had a mean height of 10.02 m and a mean DBH of 11.92 cm. At Fred’s Pass P. indicus was growing well and has persisted well with survival at 91% at age 5.5 years. P. indicus and P. macrocarpus were planted at other sites in the first year of establishment, such as at a river levee site on the Daly River where they were the only surviving species after the area experienced a flood in 1998-99. In the Marakai region P. macrocarpus did not persist on the poorly drained podzolic soil.
Further consideration should be given to these species to determine optimum provenances and silviculture.
PROJECT: Strategy and Progress of a Tree Improvement Program for African Mahogany (Khaya senegalensis) in the Northern Territory
Project Officers: D. Reilly, B. Robertson, with Dr G. Nikles of the Queensland Forestry Research Institute (QFRI)
Location: Top End of the NT.
Objectives:
To phenotypically select at least a few superior trees from each of the 24 provenances (from 11 countries of origin and one secondary) represented on the mainland (Gunn Point) and Melville Island.
To establish grafted clones of these trees in both a 'gene recombination orchard' (GRO) and in a conservation clone bank (CCB) for security, to ensure protection and use of the best of the provenance diversity present.
To establish a series of clone tests for identification of deployment clones.
To establish a clonal seed orchard (CSO) with the seemingly best 20 selected trees available to enable a seedling deployment option and culling the GRO after planting a second generation of trees.
To plant a second-cycle, base population as open-pollinated GRO families and infusions to enable future selection of superior second - generation trees for on-going improvement.
To develop protocols for the vegetative propagation of African mahogany (Khaya senegalensis).
To match K. senegalensis to sites and determine optimal silviculture, nutrition and management regimes, and wood improvement needs
To improve the expertise of DPIFM staff in genetics and tree breeding.
Introduction:
The broad genetic base of K. senegalensis in the NT consists mainly of stands planted in the early 1970s at Gunn Point and Howard Springs on about 20 hectares. Primary breeding aims are to rapidly improve stem straightness and produce diverse, second-generation progeny. The provenance trials at Gunn Point and Melville Island show that a range of natural provenances grew well in the NT. These stands have trees from 12 African countries in which the species occurs naturally (from Senegal in West Africa to Sudan and Uganda in the East) and from derived stands in New Caledonia.
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Method:
To preserve and propagate the base resource, superior trees were selected, grafted and then planted in December, 2001. This was the basis of CSO and CCB at Howard Springs and Berrimah Farm, respectively. Some 98 clones were established originally of which one flowered in 2003, eight at Berrimah Farm and seven at Howard Springs, in 2004. Seed production is expected in 2005-06. In 2003, Another 22 superior trees were selected, grafted and established in CCB, raising the breeding and propagation population to 120 clones.
This is the achievements so far in the strategy for conservation and genetic improvement of African mahogany in the Northern Territory. The strategy has two overlapping phases:
1. A simple first phase to deliver somewhat-improved planting stock as quickly as possible.
2. A long-term phase to of recurrent selection in large, improving and diverse base populations similar to that adopted successfully with Eucalyptus grandis in Florida (Eldridge et al. 1994). However, much of the seed for new base populations will be generated in a local, clonal GRO. There will be possible infusions of seed from natural provenances (especially those identified above as being absent or few in existing local stands) and possibly from other improvement programs.
To study wood quality and potential use, funding was obtained from RIRDC, DPIFM and Queensland’s Forestry Research. Initial sawing, plying and wood assessment was done in 2003. The study included 38 of the above 120 selected trees. The study has been completed. The results will be used to assist in the choice of clones to remain in CSO and the hedge gardens, which are planned for the future.
The main improvements undertaken so far include:
• Maintenance and monitoring of African mahogany and other promising species in the NHT species trials established between 1998 and 2001.
• Protection and management of CSO and CCB. Refill gaps with 22 new clones in early 2004. Obtain material from the two provenances on Melville Island which do not occur on the mainland (Chad and Benin) and incorporate in CSO and CCB.
• Establishment of hedge gardens at Berrimah Farm in 2004 to include seedlings from seed collected from 11 of the selected trees felled for the sawing study; rooted cuttings from the coppice of the stumps of the 39 trees felled for the sawing study; cuttings from CSO and CCB of the 16 trees included in the sawing study; wildings (wild seedlings) dug up from 10 different sites in the Top End.
During the 2004-05 wet season, the following components of the program were undertaken:
1. Established replicated clone tests on three sites in 2005, using rooted cuttings taken from the above hedge gardens, seed collected from locally-grown trees and striplings from the same 10 sites (in the hedges above). To ensure security of the project, the testing phase of the program (to enable provenance to site matching) has been undertaken on regional Government Research Stations at Coastal Plains and Douglas-Daly. Future testing phases of the program may also involve commercial growers on private land, if possible. This would enable more rapid deployment of untested superior clones and later deployment of genetically improved clonal material.
2. Infusion of rooted cuttings from the stump coppice of the 39 trees felled for the ‘timber evaluation study’ into the hedge garden.
3. Infusion of rooted cuttings from CSO and CCB of the 16 trees included in the ‘timber evaluation study’.
58 Technical Annual Report 2004-05
The following aspects of the improvement program are to be undertaken during the 2005-06 wet season and beyond to see the program through to conclusion:
1. Establish another hedge garden at Berrimah Farm in 2005 from stump coppice after felling of the 82 trees (that were selected and not felled in 2003) plus any other outstanding trees that may be found in mahogany plantings between 1998 and 2001.
2. Establish replicated clone tests over several sites at Katherine and Coastal Plains (with climatic and/or soil variability) in 2006, using rooted cuttings taken from both hedge gardens (120 clones). Check genotype by environment (G x E) interaction and provenance effect.
3. Relocate and expand hedges at Berrimah Farm of the better clones (from stump coppice) as revealed by the clone tests and wood studies, in preparation for production-scale collection of cuttings for the agro- forestry industry plantation program. This may start as early as 2008-09 using early results from the first clone test.
4. Establish the second-generation base population from seed collected in CSO, before any culling from all 120 clones, after heavy, general flowering. This seed would be used to establish replicated family trials, perhaps as 30 seedlings per family on at least two representative sites. These plantings will help to observe G x E interaction, and as the base for selecting some 120 superior progeny as the second generation breeding population. Planting may be possible in 2007 or 2008.
5. Cull CSO initially on the basis of the selected phenotypes and early results of clone and wood tests. Perhaps starting in 2008, but not before seed is obtained from every clone following a heavy, general flowering, for use in establishing the second-generation base population.
6. Clone testing from second-generation CSO seedlings of the better clones. It may start in 2011. On average, CSO progeny as a whole are expected to be superior to the original base. The best 30 families should yield top-rank clones that are superior to those from the original stump coppice.
In May 2004 it was proposed to expedite delivery of the first improved seed from CCB. To facilitate this it was necessary to congregate grafts of the best clones around the cluster of the seemingly very good clone numbers 16 and 122 at the south end of CCB. These putatively better clones were determined from the growth and form of the original 120 selected trees from Howard Springs and Gunn Point. Further determination of the superior clones will be gained from the ranking of the clones from the ‘Timber Evaluation Study’. The best 10 to 11 phenotypes from the original suite of 120 were chosen as putatively better clones and were physically dug up from their allocated positions in CCB and transplanted to their new positions at the south end of CCB. Survival of the transplanted clones was surprisingly high as only two trees died from the stress of re-location.
The above program has the potential to largely underpin an agro-forestry industry based on African mahogany in the Top End.
Table 1 shows the countries and provenances on which the African mahogany tree improvement program is based.
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Table 1. Provenances of Khaya senegalensis plantings at Gunn Point (Superior selected trees in brackets)
Seed code Provenance 1970-71 1971-72 1972-73 (EP 363b) (EP388) (EP420) D391 Central African Republic + (7) + (1) - D407 Uganda + (5) - - D408 Uganda (West Nile) + (3) - - S9620 Uganda (West Nile) + (2) + (3) - S10053 Uganda - - + (4) D411 Togo + (6) - - D415 Upper Volta + (4) + (4) - D416 Upper Volta + (4) + (5) - D417 Senegal + (5) + (4) - S9392 Senegal (69) + (5) - - S10066 Senegal - - + (5) S9368 Sudan + (2) - - S9687 Sudan + (5) + (5) - D477 New Caledonia - + (3) - D487 New Cal.(ex Ivory Coast) - + (6) - D522 Noumea New Caledonia - - + (4) S10050 Ivory Coast - + (5) - D480 Nigeria (Jos) - + (6) - D486 Nigeria (Yola) - + (5) - D500 Ghana - + (5) + (6)
Table 2 shows the components of the clone tests for African mahogany that were established at three sites in the NT in 2004-05.
Table 2. Summary details of the composition of Khaya senegalensis clone tests
Test material x test CT 1a (CPHRS, c. 55 CT 1b (CPHRS, c. 55 CT 1c (Douglas Daly sites – showing km SE of Darwin) km SE of Darwin) RS, c. 170 km S of clone or seedling (3 ramets/clone) (2 ramets/clone) Darwin) numbers planted early Jan. 05 planted early Jan. 05 (3 ramets/ clone) plant early July, 05 Clones from OP 246 166 (includes many 66 (includes many seedlings ex 11 of the clones common to CTs linking/common clones 38 trees selected in 1a, 1b) to CT 1a; and many 2003 in the NT links to CT 1b) plantings of the early 1970s at Gunn Pt and Howard Springs Reserves predominantly Clones from bulked 97 62 8 seed ex Weipa, Qld selects Clones ex NT 52 30 13 wildlings Other clones - - 2 Clone totals per rep 395 258 89 Seedlings ex 9/11 OP 133 per rep 112 per rep 24 per rep families of NT (9/11in 1b; 4/11 in 1c) Seedlings ex Darwin 72 per rep 110 per rep 7 per rep street trees Seedlings totals per 205 222 31 rep Grand total plants per 600 480 120 rep
60 Technical Annual Report 2004-05
Program: Extension
PROJECT: Agriculture Development and Extension, Douglas Daly
Project Officer: P. Hausler
Location: Douglas Daly
Objectives:
To provide research, development and extension services to commercial producers in the Douglas Daly region.
To create opportunities for the expansion of diversified, sustainable agriculture in the Top End.
Highlights for the year
Pastoral survey
This was a significant project undertaken throughout the wet season. The survey consisted of some 26 pages of questions and took up to three hours to complete. All Top End producers running more than 50 head of cattle or buffalo and or producing greater than 100 tonnes of hay per year were surveyed. In all 46 Top End producers were surveyed covering an area of 22 500 square km.
Silage production
Two Top End properties have cut wet season grown sweet sorghum to produce silage and are currently feeding beef cattle destined for SE Asia. Silage production reached 27 000 tonnes this year.
Production of melons and pumpkins
Cultivation is continuing at a steady rate in the Douglas Daly district with one producer ceasing production and another starting. The owners of “Ruby Downs” have diversified their operation by developing an irrigation area and leasing it to a farmer.
Field days and farm walks
Two farm walks were held this year:
• The annual farm walk around the Douglas Daly commercial farms was held in April 2005. It was very successful with over 40 people attending. Producers see this as a good opportunity to view first hand what other producers are doing. It is also a very worthwhile exercise for new and current producers to find out best commercial practices.
• Approximately 40 people attended a field day at DDRF in May 2005. This year, producers were treated to a tour of the research farm with project officers giving updates on their trials and demonstrations.
Meeting new and prospective clients
Discussions have been held with several people interested in agricultural ventures in the Top End.
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Program: Weeds
PROJECT: Improved Pasture, Fertiliser and Herbicide Demonstration
Project Officers: B. Beumer, R. Eastick and N. Hartley
Location: Carmor Plains Station
Objectives:
To evaluate suitability of Paspalum nicorae cv. Blue Dawn on Fringe country.
To demonstrate suitability and vigour of improved grass species.
To demonstrate value of fertiliser on yield of improved pastures.
To evaluate herbicide efficacy for broad-leaf weed control on second year established perennial grasses.
Participating producer: Matt Kelman
Background:
Broad-leaf weed invasion is a major constraint to the production of improved pastures. Previous herbicide evaluation identified 2, 4-D amicide, and combinations with either diuron or Brush-Off® as effective against broad-leaf weeds. However, there was uncertainty whether this would cause damage to newly-sown pasture. A trial was conducted to evaluate phytotoxicity on selected first-year sown pasture species. They were Setaria sphacelata cv. Kazangula, Digitaria swynnertonii cv. Arnhem, Digitaria milanjiana cv. Jarra and Paspalum nicorae cv. Blue Dawn. The last was also evaluated for suitability to the local land. The effect of fertiliser on establishment of pasture species was also evaluated. The demonstration site was established in the 2003-04 wet season.
Results indicated that the Brush-Off plus 2, 4-D amicide treatment provided the best weed control and maximised grass yields for all pasture species, and that the early herbicide application was more effective for weed control than the later application. Although there was minor herbicide phytotoxicity on the grass, it was insignificant compared with the no herbicide control, where grass yields were extremely poor, due to weeds. Since Blue Dawn gave poor yields across all fertiliser and herbicide treatments, further evaluation of spread off-site and response to burning was not necessary. There was no marked effect of fertiliser application on pasture establishment, maybe due to interaction with herbicide efficacy, weed establishment and residual nutrition from previously established calopo (Calopogonium mucunoides).
In the 2004-05 season we continued the pasture species evaluation and assessment of the effect of fertiliser due to the expected decline in residual nutrition at the site. The herbicide evaluation was modified to only one application time, as a replicated experiment on timing of herbicide application was conducted at another site (see Kumbyechance pre-schedule).
62 Technical Annual Report 2004-05
Method:
Design
Four established improved grass species in 4-m wide rows 32 m long with 5-m wide laneways in between to form a block 40 m x 31 m.
The block was bisected across the rows to form two portions – fertilised and unfertilised. The fertilised portion was applied with 200 kg/ha fertiliser in early December, consistent with the previous season. It was on the northern half (flood-plain side) of the site.
Then each of these two portions had the following herbicide treatments sprayed in 4-m wide runs across the pasture rows.
Table 1. Herbicide treatments
Herbicide treatment Rate/ha Control – no herbicide 24-D amicide only 800 mL Brush-off and 24-D amicide mix 10 g and 800 mL Diuron 500 and 24-D amicide mix 2 L and 800 mL
The fertiliser and herbicides were applied on 2 December when grasses and weeds were approximately 15 cm tall, and was duplicated over the same plots as they had been applied last season. A 1000 wetter was added to each herbicide treatment.
Measurements
Visual assessment (ratings and photos) of herbicide efficacy and phytotoxicity was taken on 16 December, 2 weeks after herbicide application.
Biomass from a 1m x 0.5 m quadrat per plot was cut at the end of the wet season to compare relative biomass between treatments.
Results:
Data collation and analyses is currently being conducted.
Conclusion:
Observations indicated that the Brush-Off and amicide mix provided the best weed control and the highest pasture grass biomass, with all species persisting, and re-establishing well after the plots were burned during the dry season.
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PROJECT: Broadleaf Weed Control in Perennial Grass Pastures
Project Officers: R. Eastick, N. Hartley and B. Beumer
Location: Kumbyechance
Objectives:
To determine the optimum herbicide or herbicide combination for effective broad-leaf weed control in newly sown and established perennial grass pastures, as a basis for herbicide recommendations to farmers.
To conduct research on a commercial farm to facilitate extension of results to industry.
Participating producers: Malcolm Bishop and Bob McDonald.
Background:
Invasion by broad-leaf weeds is a major constraint to the production of perennial grass pastures. A number of broad-leaf herbicide studies in the past have indicated that best results were obtained by using a diuron and 2, 4-D mix, especially to also effectively control annual grass weeds such as Pennisetum pedicellatum. The Brush-off and 2, 4-D mix also gave good results and was probably the most cost-effective treatment. Ideally, these herbicides should be applied early in the growing season, when weeds are small and lower rates of application are effective.
However, it was uncertain if these herbicides would cause damage to newly-sown pasture, especially when applied in the first month after pasture germination. The label on Brush-off states that severe damage may occur to newly-sown pastures; diuron acts on grass at certain rates and on certain species; some grass and cereal species have listed tolerance levels to 2, 4-D amicide.
In the 2003-04 season, we applied these herbicides individually and in combination, at different rates and times, at Carmor Plains Station to evaluate phytotoxicity on selected first-year sown pasture species and to provide further information on efficacy on broad-leaf weeds.
Generally, early herbicide application provided the best weed control and higher pasture yield than later application. There appeared to be moderate grass damage from the diuron + 2, 4-D treatment, and minimal damage from the Brush-off + 2, 4-D treatment. However, it was difficult to quantify results due to weed competition. The control plots, where no herbicide had been applied, indicated that not applying herbicide would cause a greater reduction in yield through weed competition than herbicide damage in high weed densities
This experiment is a continuation of previous work on a Douglas Daly Property, Kumbyechance, to enhance farmer relevance and liaison. The paddock had heavily grazed sabi grass and was severely infested with senna, Sida spp and Hyptis at the start of the trial. The farmer intends to spray for broad-leaf weeds in an effort to re-establish the sabi grass. The trial will evaluate pasture establishment, herbicide efficacy and effect of management.
64 Technical Annual Report 2004-05
Method:
Experimental design Randomised split-split plot
Site Kumbyechance, Douglas Daly, Area 60 m by 80 m. Plot size 8 m by 7 m
Fenced area 80 m by 100 m
Treatments Main plot: Pasture species • Jarra • Sabi • Strickland
Sub-plot: Herbicide (details in Table 1) • 2,4-D amicide only • 2,4-D amicide + Brush Off® • 2,4-D amicide + diuron • Pasture only – hand-weeded • Pasture + weed – no herbicide applied • Atrazine was applied as a single strip for observation outside the experimental plot area.
Sub-sub plot: Time of application • Early (four weeks after emergence) • Late (12 weeks after emergence)
The area was slashed on 7 December 2004 to top the high standing dead weed biomass (mainly Sida acuta and Hyptis). The remaining sabi was sprayed with Round-up450® at 5 L/ha (+0.25% LI700) on 14 December after the initial rains and then the area was fenced. It was disked on 22 December and again on 14 January 2005 to kill newly-emerging weeds, predominantly Senna and Sida. Pasture species were hand-sown and fertiliser (200 kg/ha 12-5-14+trace) was hand-spread, on 15 January, followed by light harrowing.
It was intended to apply herbicides twice. However, due to a prolonged dry spell in January and February, early fertiliser application was delayed. So only a single application was carried out on 22 March, at the high rate only, when grass and weeds were 30-40 cm tall. Herbicides were applied using the Marrakai Extension Quad bike and 4 m boom, at 120 L/ha output with a 40 L tank mix.
Measurements
An assessment of present weeds and their growth stage was recorded prior to spraying.
Visual ratings (0-10 for no damage to total kill) were conducted approximately two weeks after herbicide application.
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Table 1. Herbicide use and cost
Rate Cost ($/unit Cost Trade name Active ingredient Adjuvant (product/ha) herbicide) ($/ha) E*: 1.5 & 0.8 Diuron (flow’) $23.85 Diuron (500 g/L) L* $12/L BS1000 and 2, 4-D 2, 4-D amicide (625 g/L) $7.30/L (100 mL/100 L) amicide L: 3 & 1.6 L $47.70 E: 7.5 g & 0.8 $8.45 Brush-off and 2, Metsulfuron (600 g/kg) L $0.35/g BS1000 4-D amicide 2,4-D amicide (625 g/L) L: 15 g & $7.30/L (200 mL/100 L) $16.90 1.6 L E: 0.8 L $5.85 BS1000 2, 4-D amicide 2,4-D amicide (625 g/L) (200 mL/100 L) L: 1.6 L $11.70
Nu-trazine E: 2 & 0.8 L atrazine (500 g/L) Flowable and 2, 2,4-D amicide (625 g/L) 4-D amicide L: 4 & 1.6 L * E = early; L=late
Final harvest was taken on 16 May and divided into desirable grass species and broad-leaf weeds, which were predominantly Sida and buffalo clover, with isolated Senna.
Cattle were allowed access to the fenced site over the 2005 dry season to simulate a realistic commercial situation.
Results:
Data collation and analyses is currently being conducted.
Conclusion:
Jarra and Strickland established well, whereas sabi was very patchy. Observations indicated that the diuron and amicide mix provided excellent grass (summer grass species and Pennisetum pedicellatum) and broad- leaf weed control (mainly Sida acuta), but caused unacceptable phytotoxicity to all improved grass species. Consistent with previous seasons, the Brush-Off® and amicide mix provided the best weed control with minimal pasture damage – although infestation by summer grass (Digitaria sp.) was evident. It is intended to assess the second year establishment of these pasture species, and to repeat the herbicide treatments in the 2005-06 season, particularly to evaluate the time of application treatment which was not conducted this season.
66 Technical Annual Report 2004-05
PROJECT: Weed Management Strategies for Cavalcade – Mt. Keppler
Project Officers: R. Eastick, N. Hartley and B. Beumer
Location: Mt Keppler
Objective:
To evaluate integrated weed management strategies in a Cavalcade production system.
Participating producer: Don White
Background:
This project commenced at Mt. Keppler in the 1997-98 wet season, at which time herbicide efficacy in conventional till Cavalcade was evaluated. No-till treatments were incorporated in subsequent years. A grass rotation (Digitaria milanjiana cv. Jarra) was sown in the 2000-01 wet season, and maintained in 2001-02 with successful control of broad-leaf weeds. Half the Jarra area was re-sown with Cavalcade and split into conventional till and no-till halves in the 2002-03 wet season. Spinnaker applied pre-emergence was compared with no herbicide application under the two tillage regimes.
In the 2003-04 season, the Jarra area was maintained for another year to allow further broad-leaf weed control and enhance the effect of a grass rotation on subsequent weed dynamics in a Cavalcade crop. Within the Cavalcade area, the tillage and herbicide were repeated, with the addition of a Spinnaker post- emergent treatment. This season, the entire area was sown with Cavalcade to continue herbicide evaluation and to determine the effect of the length of a grass rotation on weed dynamics in a Cavalcade production system.
Method:
Experimental design
Un-replicated split-split plot
Main plot Grass rotation 1. Cavalcade following two years of Jarra and two years of Cavalcade 2. Cavalcade following four years of Jarra
Sub-plot Tillage treatments 1. Conventional 2. No-till
Sub-sub plot Herbicide treatments: 1. Crop and weed the control 2. Spinnaker (700 g/kg imazethapyr) pre applied immediately after sowing. Rate 140 g/ha 3. Spinnaker post applied at the three to five leaf stage at two weeks after sowing. Rate 140 g/ha. Hasten® as wetter (5 mL/100 L).
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Land preparation
The Cavalcade and Jarra pastures were mown and baled for hay at the start of the 2004 dry season. Roundup Max 520 was applied at 4 L/ha (+0.25% LI700) to the Jarra, and to the no herbicide treatments on 9 December for mulch management. Emerging vegetation in the previously herbicide treated areas, where there was less biomass allowed to establish to develop suitable mulch levels for no-till treatments, was applied with a knockdown herbicide on 13 December.
Areas to be sown conventional till were cultivated on the 22 December 2004.
The entire area was sown with Cavalcade at 16 kg/ha (germination rate of 43%) and fertilised with 200 kg/ha of Rustica Pluss 12-5-14 + trace on 13 January.
Herbicide application
Spinnaker® pre-emergent was applied immediately after sowing.
Spinnaker® post-emergent was applied on 24/01/05.
Herbicides were applied with the Marrakai Extension quad bike and 4 m boom.
Measurements
Biomass (hand-harvested) was done twice.
1. Four weeks after sowing (four and two weeks after herbicide application for the pre- and post-emergent treatments, respectively) 7/2/05.
2. Twelve to16 weeks after sowing, 19/04/05. Harvest was on four 1 m x 0.5 m quadrats and samples were sorted into Cavalcade, Senna, other broad- leaf weeds and grass weeds.
Results:
Data has been collated, but analyses are continuing.
Conclusion:
Observations indicated that broad-leaf weed emergence was less in the longer-term Jarra rotation than after the two year rotation. Application of Spinnaker® appears to select for increased Senna establishment over time. It is proposed that the area be established as self-sown Cavalcade in the 2005-06 season, and comparison of pre-wet season applied herbicide treatments be conducted in a replicated experiment.
68 Technical Annual Report 2004-05
PROJECT: Pre-Wet Season Herbicide Management in Cavalcade
Project Officers: R. Eastick, N. Hartley and P. Shotton
Location: Bay 7, Douglas Daly Research Farm (DDRF)
Objective:
To determine the suitability of pre-wet season application of Spinnaker® or Flame® for weed management in self-sown Cavalcade.
Background:
The project was initiated in the 2003-04 season to assess weed control and phytotoxicity of Cavalcade from pre-wet season application of Spinnaker700WDG® or Flame® at two rates in a self-sown Cavalcade crop. The first herbicide application was on 12 September 2003, with subsequent applications every two weeks until 7 November, coinciding with the time of first rain#, which corresponded to 54 days after the time of first herbicide application. Cavalcade and weeds were harvested on 20 December 2003 (45 days after rain) and 5 February 2004 (90 days after rain), to determine herbicide phytotoxicity. Time elapsed after rainfall has implications for degradation of herbicide.
Results indicated that at the initial harvest, both rates of Flame (400 and 800 mL/ha), and the Spinnaker High (280 g/ha) were somewhat detrimental to Cavalcade yield. However, by the time of final harvest, the Flame High was the only treatment where a decline in Cavalcade yield was observed, and all other treatments had a compensatory yield of approximately 7 t/ha.
Weed control in all treatments was excellent, particularly of grass weeds, even in the first herbicide applied strips. Senna was the only broad-leaf weed present, although density appeared to be reduced compared with the control treatment. This indicated that residual activity of imidazolinones was maintained until the commencement of rainfall, which initiated degradation of the chemical.
Overall, application of an imidazolinone herbicide prior to the commencement of the wet season appears to have potential in self-sown Cavalcade crops. We decided to further examine this option by applying selected ‘best-bet’ time and rate of applications.
The aim is to develop a best-bet strategy where a recommendation can be made on time of application with confidence that rain would not occur by that date, but that enough residual activity of the herbicide would remain when the rain does come.
Method:
Experimental design and location
Herbicides will be applied in demonstration strips in Bay 7 at DDRF.
Treatments
Herbicides 1. Spinnaker 700WDG® (700 g/kg imazethapyr) • @140 g/ha (maximum recommended rate; 98 g/ha a.i.) 2. Flame® (240 g/L imazapic) • @400 mL/ha (maximum recommended rate; 96 g/ha a.i.)
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Time of application
Long term climatic analysis indicates that the ‘start of the wet season’ at DDRF is on 2 November (T. Schatz: 50 mm in two weeks), so timing of pre-wet season herbicide treatment application was determined from this date, and was applied at two times: six weeks and three weeks prior to the predicted start of the wet season. This corresponded to:
• T1: 21 September (42 days before). • T2: 12 October (21 days before).
Spinnaker® was also applied post-emergent as soon as possible after Cavalcade germination (@1-leaf stage) 9/11/004.
This provides a total of five treatments, plus a control, where no herbicide was applied.
Land preparation and herbicide application
Bay 7: The third bay from the gate was used. This was cut for hay in the 2003-04 season. Cattle grazed this area in the 2004 dry season, resulting in low biomass coverage (<1 t/ha).
Each plot was 16 m wide (four boom runs), with herbicides applied across the bay.
Herbicides were applied according to treatment outline.
Measurements
Biomass cuts and damage ratings for weeds and Cavalcade were conducted for each treatment (time of application x herbicide) 45 and 90 days after effective rainfall to be consistent with last season’s measurements.
Four 0.5 x 1 m quadrats in each plot were taken on the 12/5/05, and separated into Cavalcade and weed biomass.
Results:
Data has been collated, but analyses are continuing.
Conclusion:
Results from this site supported those from the previous season that indicated that application of Spinnaker® prior to the commencement of the wet season has the potential for weed management in a self-sown Cavalcade crop. Flame® was considered to produce unacceptable Cavalcade phytotoxicity. It is intended to conduct a replicated experiment assessing Spinnaker applied at various time intervals in the 2005-06 wet season. This will facilitate development of a potential additional weed management tool in a Cavalcade production system, where Spinnaker® can be applied late in the dry season to allow increased farmer flexibility in weed control operations.
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SERVICE: PASTORAL PRODUCTION
Program: Native Pasture Management
PROJECT: Fire and Vegetation Management in the VRD
Project Officer: R. Cowley
Location: Victoria River Research Station (VRRS)
Objectives:
To understand the long term impacts of burning on woody plant cover and pasture condition.
To develop practical burning management guidelines for land managers.
To increase the use of fire as a tool to manage woody plants in the pastoral industry of the VRD.
Summary:
Woody growth in the absence of fire will reduce pasture production as a result of increased competition for soil moisture and/or nutrients. Although many woody communities are adapted to periodic burning, the prescribed use of fire has been demonstrated to have an important role in the management of tree-grass balance and pasture condition. Guidelines concerning its use as part of a management system have been developed based on results from the first six years of the fire trials at VRRS. To understand the longer term effects of implementing recommended fire regimes, the fire trials at Kidman are being continued with a lower level intensity of vegetation monitoring.
Method:
Red soil and black soil plots are burned at two, four and six-year intervals in the early or late dry season. Pasture is monitored every second year before burning to get an estimate of pasture condition and fuel load. Yield, pasture composition, cover and grazing are assessed over all plots in the early dry season (July). Yield on plots to be burned is assessed in the late dry (October). Aerial photographs are taken of the plots prior to burning in July.
Results:
Burns conducted in July 2005 were patchy on the red soil plots in Conkerberry paddock due to patchy cover and low yield. In contrast good even burns were achieved on the black soil plots in Rosewood. Pasture was assessed and aerial photos were taken in July 2005. Data has been collected, but not yet analysed.
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2 yearly burns Unburnt Unburnt
Figure 1. Aerial photo of Rosewood fire plots in June 2005
Higher shrub cover is evident in the unburnt plots compared with the burnt plots.
PROJECT: Grazing Regimes to Maintain Biodiversity in Mitchell Grasslands
Project Officers: R. Cowley and C. Materne
Location: Mt Sanford Station, VRD
Objectives:
To determine the impact of stocking rate and distribution of grazing pressure on the biodiversity of flora and bird species in the Mitchell grasslands.
To formulate best-practice stocking and grazing guidelines for the conservation of biodiversity values.
To improve the knowledge, and understanding of land managers about maintenance of biodiversity in production systems.
To facilitate appropriate development to enhance profitability and ensure conservation of biodiversity.
Background:
Cattle-grazing influences plant and animal diversity in Mitchell grasslands and in pasture lands generally, in the Northern Territory. However, land managers still lack critical information about management to maximise the conservation of biodiversity within production systems. This currently constrains the development and implementation of integrated management regimes to enhance regional conservation. Diversity of plants and birds was surveyed in the Mt Sanford grazing trial in the 12%, 23%, 34% and 45% utilisation treatments. Plant and bird diversity surveys were conducted in April and October 2002 and 2003.
Results:
Ground cover has decreased in the higher grazed paddocks compared with the lighter grazed paddocks. However, the effect of this is rarely reflected in bird diversity or abundances. This is probably due to the good 72 Technical Annual Report 2004-05 condition of the higher grazed paddocks before the trial started, and the delay in the effect of an altered habitat (due to grazing) on breeding success, which takes a few years before it affects bird numbers. Of interest however, is that aerial insectivores were more likely to be found near waters, while the grassland raptor, the spotted harrier, was more likely to be found in lightly-grazed paddocks and in areas with higher cover. Further surveys are needed to allow for the long-term impact of habitat change to be detected on bird numbers.
There were no significant trends in total species richness or diversity with pasture utilisation in the first two years. However, species composition was beginning to differ in response to the effects of pasture utilisation. From 2002 to 2003 the proportion of all plant species with a greater than 5% palatability, increased in the low utilisation areas (12-23%), but decreased in the high utilisation areas (35-45%). In 2003 six unpalatable or short-lived species which tend to increase under high grazing, were more abundant in the higher utilisation areas (Table 1). This contrasts with four palatable species (which tend to decrease under higher grazing) that were more abundant in the low utilisation areas. The results of the first two years suggest that the rate of utilisation affected species composition, and that such effect increased with time.
Developments
The data from 2002 and 2003 shows the initial effects of treatment. More surveys in 2006 should provide clearer results.
Table 1. The effect of low and high pasture utilisation on median frequency of species in 2002 and 2003
2002 2003 Species Low High Low High utilisation utilisation utilisation utilisation Increasers Brachyachne convergens 9.38 31.25* Chrysopogon fallax 3.12 21.87* Desmodium muelleri 0.00 6.25** Flemingia pauciflora 6.25 43.75** 6.25 31.25* Glycine falcata 0.00 6.25** Heliotropium plumosum 0.00 3.13* Polymeria longifolia 0.00 12.50** 0.00 6.25* Decreasers Ipomea nil 3.44 0.00* 6.25 0.00** Iseilema vaginiflorum 43.75 18.75* 65.62 34.37* Iseilema windersii 3.13 0.00* Panicum decompositum 9.38 0.00* Mann-Whitney U test, N = 6, *P<0.05, **P<0.01.
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PROJECT: Barkly Tableland Burning Trial
Project Officer: C. Materne
Location: Alexandria Station
Objectives:
To measure the impact of low intensity, late wet season fires and high intensity, dry season fires on Mitchell grasslands and woody plant species in Buchanan paddock on Alexandria station.
To demonstrate the application of prescribed burning in the extensively grazed Mitchell grasslands of Buchanan paddock and its use in pasture management.
Background:
Traditionally, pastoralists considered the Mitchell grasslands of the Barkly Tableland as too valuable, in terms of cattle feed, to burn. Research in other regions suggests that Mitchell grasses (Astrebla spp.) recover rapidly after burning and that cattle grazing on burnt pasture usually perform better during the wet season, than those grazing un-burnt pasture. Now with this information, along with anecdotal evidence that woody tree and shrub species are beginning to increase and encroach onto Mitchell grasslands, certain pastoralists are of the view that not enough fire is used on Mitchell grass on the Barkly Tableland.
The aim of the Alexandria burning trial is to determine the impact of seasonal prescribed fire on native tree and shrub species, pasture composition and quality, and cattle grazing characteristics of Mitchell grasslands on the Barkly Tableland.
Developments
Plot trial
Four sets of three plots with three different treatments have been established. Pre-burn pasture and shrub data was collected in April and October 2002, and April and October 2003. Post-burn data was collected during October 2002, April and October 2003, and April and December 2004. All planned burns have been completed for the trial and include four low intensity, late wet season burns (April 2002 and April 2003) and four high intensity, late dry season burns (October 2002 and October 2003). Analysis of the data is continuing. All results have been provided to management at Alexandria Station. The results form the basis for a Section on fire in the Barkly Rangeland Management Course, presented at the 2005 Barkly Head Stockmen Tour. The information was also included in a publication titled “Mitchell grasslands: assessing quality and quantity.
Demonstration trial
Implementation of a paddock-scale-burning regime commenced in October 2001, followed up with further burns in October 2002. Additional prescribed burning was planned for October 2003 and 2004. However, due to below average growing seasons, no burns were carried out. Observations indicate that Mitchell grasslands recover well after burning followed by an average rainfall season. Only minimal differences under grazing were visible in April 2004 between the burnt and un-burnt areas of 2001.
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Program: Grazing Management
PROJECT: Identifying Optimum Levels of Pasture Utilisation on a Commercial Scale
Project Officer: R. Cowley
Location: Pigeonhole Station, VRD
Objective:
To identify optimal levels of pasture utilisation on a commercial scale.
Background:
The Mt Sanford grazing trial has indicated that pasture utilisation rates of up to 20% can be safely implemented with significant increases in beef production and profit per unit area. This is substantially higher than the industry average of 12.5% in the VRD (based on a DPIFM survey of 12 properties in the VRD in 1997) and suggests there is considerable room for increasing cattle production in the region. However, results from the Mt Sanford trial may reflect a bias because of better facilities at the research trial with its relatively small paddocks (4-8 km2) compared with commercially viable scales of production. This project aims to test the applicability of higher utilisation rates on a larger scale at Pigeonhole Station, VRD. It is part of a joint project between Heytesbury Beef, CSIRO and DPIFM. It is funded by Heytesbury Beef and MLA. Pasture condition and cattle production are assessed.
Method:
Animals are stocked according to treatment (15%, 20%, 25%, 30% and 40% utilisation) in May, after yields are assessed. Animal production is assessed at each muster. Pasture is monitored in May and October on a grid pattern across the site. Transects running north south are spaced 500 m apart and 2x 2 m quadrats are assessed every 100 m along transects. This gives approximately 400 quadrats/20 km2 paddock (20 points /km2).
Results:
Site infrastructure was completed and paddocks were stocked according to treatment in October 2003. The trial has been in place for two and a half years.
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Land condition
In May 2005 yield, cover and palatable yield generally declined with utilisation rate (Figures 1-3).
3500 May 2005 3000 May 2004 2500 2000
2005 1500 1000 500 Total yield (kg/ha) May May (kg/ha) yield Total 0 10 20 30 40 Utilisation rate %
Figure 1. Yield in May 2004 and May 2005 at the Pigeon Hole project trial site
90 May 2005 May 2004
70
50 % May % May 2005
Understorey ground cover cover ground Understorey 30 10 20 30 40 50 Utilisation rate %
Figure 2. Understorey cover in May 2004 and 2005 at the Pigeon Hole project trial site
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1000 May 2005 May 2004 800
600
400 May 2005 200
Palatable yield (kg/ha) 0 10 20 30 40 50 Utilisation rate %
Figure 3. Palatable yield in May 2004 and 2005 at the Pigeon Hole project trial site
Animal production
By May 2005 the utilisation rate was beginning to affect weight gain of suckling calves. Weight gain of suckling calves in the 40% utilisation treatment was half that of the 15 and 20% utilisation treatments in the May 2004-05 wet (Figure 4).
160 2004 dry 140 2004/05 120 100 80
cow (kg) cow 60 40 20 Weight gain of calves ofon calves gain Weight 0 10 20 30 40 50 Utilisation rate %
Figure 4. Weight gain of suckling calves in the 2004 dry season and the 2004-05 wet season
The effect of utilisation on animal productivity on both an individual and per land unit area basis over the 2004- 05 wet season is shown in Figure 5. While there is considerably less individual gain in the highest utilisation treatments, the highest kg/km2 was at 40% for the last wet.
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140 2500
120 2000
100 2
1500 80
60 1000
40 Individual weight gain of growers km per produced kg Weight gaingrowers (kg) Weight gain per land unit area 500 20
0 0 15 20 25 30 35 40 Utilisation rate %
Figure 5. Animal productivity per individual animal and per land unit area in the 2004-05 wet season
However, while the high utilisation treatment was the most productive for last year, it came at a cost. The combined effect of fire and high stocking rates has led to large decreases in cover and yield in the 30% and 40% utilisation treatments. The reduced pasture availability in the 30% and 40% utilisation rate paddocks has meant that stocking rates had to be markedly reduced this year. Above 25% utilisation, stocking rates actually decrease with increasing utilisation. If individual animal performance continued to follow the trend with utilisation seen this wet, future animal productivity per land unit area will decline markedly on the highest utilisation paddocks, due to the low stocking rates that can be maintained. Longer term trends will be interesting to follow in the next few years.
PROJECT: Risk Management Tools for Grazing Land Management
Project Officer: R. Cowley
Objective:
To develop a property scale decision support and risk management tool for grazing land management.
Background:
Pastoral properties in northern Australia have large numbers of extensive paddocks, often containing many land types. Predicting the impact of a suite of interacting factors (seasonal and spatial variability, stocking rates, fire and access to water), on the risk of overgrazing, is a complex task. The aim of the project is to make it easier for land managers to make sustainable stocking rate decisions on a seasonal and long-term basis. To do this we are developing a property scale decision support and risk management tool. QDNRM, QDPIF, Heytesbury Beef, NAPCO, Stanbroke and AACo are collaborating to develop the tool to ensure relevance and usefulness to producers.
Results:
In May 2003 a workshop was conducted to develop the tool. Participants included developers of the Paddock Grasp (DNRM), the Stocking Rate Calculator (DPIFM), and other potential users of the tool – QDPIF and land managers.
78 Technical Annual Report 2004-05
The workshop identified:
• desired functionality • projected use • potential outputs • structure • inputs and outputs of the tool engine • scenarios the tool would analyse • requirements for the platform of the tool.
The engine for the tool was developed by June 2004. The Cedar version of GRASP is packaged within the tool. The engine is able to work through the Internet to call up QDNR climate files for specified locations, and then to run GRASP for each of the combinations of land type and climate cells, then send a summary to the user. The tool allows for security specification, so that people can only access the information relevant to their group. Inputs include polygons of land type and infrastructure, as well as mrx files, which have management and land system information.
Currently the package does not include a user interface allowing the setting of input parameters or presentation of output data – it only allows base calculations and tables. However, four scenarios have been developed to demonstrate the capability of the software to users.
Future development
The next step will be to develop a user interface and test the software with potential users and project collaborators.
The challenge is to develop an ongoing business model for the risk management tool to promote ongoing investment and therefore ownership of the software.
PROJECT: Developing Sustainable Carrying Capacities in the NT
Project Officers: A. Kennedy and C. Materne (Alice Springs), R. Allan and G. Nash (Barkly), C. Smith and R. Cowley (Sturt Plateau)
Location: Alice Springs, Barkly and Sturt Plateau
Objectives:
To develop methods for the objective assessment of carrying capacity and to calibrate pasture growth models for the Sturt Plateau, the Barkly region and the Alice Springs region.
To transmit the results to pastoralists to enable them to make appropriate decisions on seasonal and long-term stocking rates.
Background:
There is potential in the NT cattle industry to increase production through subdivision and intensification of land use. However, land intensification in other states has sometimes led to unviable small blocks and extensive land degradation, due to an over-optimistic assessment of land capability. To facilitate sustainable development of the NT cattle industry it is therefore imperative that we have an objective and transparent method for estimating carrying capacity, particularly where properties are being subdivided.
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This project aims to calibrate the GRASP model to facilitate estimation of sustainable carrying capacities in important grazing pasture types of the NT in the Barkly, Sturt Plateau and Alice Springs regions. The GRASP model is calibrated through the collection of pasture, soil and meteorological data from small exclosures called SWIFTSYND sites. These exclosures have been set up on areas that represent different land systems and vegetation types in order to obtain a broad viewpoint across the region.
Monitoring events (harvests) are conducted at four times throughout the year except for the Alice Springs region where harvests are conducted two-monthly. The timing of harvests depends on seasonal conditions. At each harvest, pasture, soil and rainfall data is collected from the sites.
Alice Springs
Method:
Six sites were constructed on four stations and the Old Man Plains Research Station during 2004-05. They represented the following land systems: Alcoota (Alcoota Station), Ebenezer (Mt Ebenezer Station), Muller (Old Man Plains Research Station), Outounya (Umbeara Station), Renners (Deep Well Station) and Sandover (Alcoota Station).
Results:
Due to the lack of rain in the Alice Springs district, data has been collected from only two of the six sites.
Developments
During the 2005-06 financial year, four additional sites will be constructed.
Barkly/Tennant Creek
Method:
Eight monitoring sites have been constructed in the Barkly region. These sites are located at Beetaloo, Benmara, Helen Springs, Newcastle Waters and Rockhampton Downs stations. The land systems represented include: Barkly, Creswell and Wonorah/Barkly1 land systems.
Results:
Monitoring site infrastructure was completed in December 2004.
As of August 2005, all sites (excluding Benmara) have been monitored up to harvest 3 stage. A species list has been compiled for each site.
Developments
Seasonal data for 2004-05 will be analysed at the end of harvest.
More sites are to be developed on the Barkly region. Work will start in September 2005.
Sturt Plateau
Results:
Currently there are six SWIFTSYND sites around the Sturt Plateau on four different land systems. We are currently selecting five more sites this month. The selected land systems are Banjo, Larrimah, Sturt, Bulwaddy and Elsey. Together, they represent 71% of the total Sturt Plateau region.
80 Technical Annual Report 2004-05
Three of the four harvests for the first year (2004-05) have been completed. The fourth is scheduled for next month. As yet there is insufficient information to begin modelling with GRASP. However, we have collected pasture (total standing) dry matter (kg/ha) data which shows patterns developing between the land systems (see Figure 1).
3500
3000
2500
2000 Total Standing Dry Matter (kg/ha) 1500
1000
500
0 Harvest 3 (May/June) Harvest 2 (Feb) Y D T Harvest 1 (Dec) D R Y A U D H T D A H W S A A Y L IM M E U W R I L S B R R L t U r A R E u B L A t t l r i L S u o l t t i s o s S e k s t c s w W a la lo E B l e Y Landsystem
Figure 1. Total standing dry matter (kg/ha) during growing season 2004-05 in the Sturt Plateau region
Soil moisture cores have been taken from every site which will become an important parameter once modelling begins.
Complete species lists and herbariums have been compiled for each site.
Developments
Five more sites are planned for next year’s records. These will replicate existing land systems as well as investigate new land systems (Banjo land system).
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PROJECT: Carrying Capacity – Testing Methods of Assessing Long Term Carrying Capacity on Kidman Springs
Project Officers: R. Cowley and K. McCosker
Location: Victoria River Research Station (VRRS)
Objective:
To assess the long-term carrying capacity at VRRS as a test case for estimating long-term carrying capacity using pasture growth models.
Background:
The Grazing Land Management course recommends a method of determining carrying capacity based on using a predetermined safe utilisation of averaged modelled pasture growth. We can already model pasture growth for many land types in the VRD, and at VRRS. We also have some estimates of safe utilisation rates based on grazing trials at Mt Sanford in the VRD and in northern Queensland. This provides a unique opportunity to test the carrying capacity methods at VRRS.
Method:
An initial assessment of carrying capacity was done in June 2002. Stocking rates were then set according to this estimated long-term carrying capacity in 2003. To assess the sustainability of the estimated carrying capacity, pasture is monitored every May, and cattle are assessed in May and September.
By mid 2004 there were concerns about the sustainability of the implemented stocking rates, due to poor or declining pasture and cattle condition. Based on this feedback, a re-evaluation of the carrying capacity was conducted in November 2004, reviewing some of the previous assumptions and testing for the sensitivity of the carrying capacity estimate.
Results:
Pasture has been monitored in 12 paddocks every May, since 2003.
The 2004 review of the carrying capacity estimate for VRRS found that the initial assumptions of a 5-km grazing radius and 25% utilisation for black soils were not conservative enough. The latest carrying capacity estimate assumes a 3-km grazing radius and 20% utilisation on black soils. The effect of pasture condition on pasture growth was assessed, but did not influence previous estimates. Tree basal area was also measured, but did not generally differ from the initial assumptions, and hence had little impact on modelled pasture growth.
The 2004 carrying capacity estimate was 25% lower than the 2002 estimate and illustrates the high sensitivity of carrying capacity to relatively small changes in the utilisation rate, particularly if the land type is common and very productive.
Output
Cowley, R. A. and Bryce, D. (2004). Kidman Springs carrying capacity estimation using pasture growth models.
82 Technical Annual Report 2004-05
PROJECT: Rockhampton Downs Alternating Watering Point Trial
Project Officer: R. Allan
Location: Rockhampton Downs Station
Objectives:
To investigate the cost benefit relationship in converting a paddock from a traditional continuous grazing system to a water-point controlled rotational grazing system that incorporates wet season spelling.
To investigate the effects of increased watering points and periods of plant rest on pasture utilisation and condition
To improve grazing management of Mitchell grasslands by increasing watering points to better control cattle grazing behaviour and to spread grazing pressure across the entire paddock.
Background:
The Australian Agricultural Company established a five-year trial to investigate the effects of increased watering points and periods of plant rest on pasture utilisation and condition. A 536 km2 paddock was divided into two with one of the new paddocks continuing under current management practices. The other paddock will operate under the alternating watering location management practice. This aims to move cattle around the paddock by having only one of the five watering points operating at any time within the paddock.
The new watering points have been created by turning off existing troughs at bores and pumping the water to new troughs approximately 4 km away in areas traditionally not grazed. At these locations water is stored in 30 000-gallon tanks. Over time, it is expected that existing watering points will experience an increase in perennial grass species cover closer to the bore as a result of reduced periods of prolonged grazing pressure. As the cattle are being strategically moved around the paddock, pasture can be spelled for greater periods than current management practices allow.
Problems experienced in the first year of the new management system have originated from the difficulties experienced when trying to move cattle from one watering point to the next. The high levels of labour required impacted on station operations and made it impractical as an alternative management system. Labour was required to hold cattle on the new watering point as they continually wanted to return to the watering point from which they had been moved.
DPIFM is assisting with pasture and animal data collection and analysis.
Developments
Initial collection of baseline pasture data was completed at the end of the dry season, 2004. This assessment observed estimated yield, species present, ground cover and percentage perennial species. Pasture data was also collected in April 2005.
Weight and pregnancy records were taken for 10% of the cattle in the treatment and control groups.
Initial summaries of the data indicate that pregnancy rates were lower in the treatment group although cattle weights were similar between groups.
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PROJECT: Newcastle Waters Rotational Grazing
Project Officer: R. Cowley
Location: Newcastle Waters Station (NWS)
Objective:
To compare rotational versus continuous grazing systems in northern Australia
Background:
As demand for cattle grows in northern Australia, particularly in the live export market, cattle producers are looking to increase production, whilst maintaining or improving environmental sustainability. Cell grazing and rotational grazing are systems that promise to allow greater carrying capacity through monitoring and rest of pastures. As cell grazing is a relatively new concept in the Northern Territory cattle industry, there is great interest in the workability of such a system on local landscapes.
In 2000, NWS began to set up cell grazing in two paddocks. This was in response to a perceived need for more intensive handling of stud weaners, and better utilisation of pastures. The sites were old holding paddocks on the Barkly stock route, and have since been used by NWS as stud paddocks. Baseline vegetation data was collected prior to cattle entering the cell and DPIFM assisted with the continued monitoring of pastures within the cell and a control. Both vegetation condition and cattle production are monitored.
Results:
The trial has now finished. Vegetation data has been collected from four paddocks within the cell and from a control paddock in May and October 2003, May and October 2004 and May 2005. Cattle production has been assessed twice yearly in May and October using weights of indicator steers in the cell and control paddocks.
Cattle and most vegetation data has been summarised. Management requirements, infrastructure costs and ongoing inputs for the different grazing systems, as well as a full economic and statistical analysis are yet to be completed for the project.
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Program: Herd Management
PROJECT: Understanding and Improving Heifer Fertility in the NT
Project Officer: T. Schatz
Location: Victoria River Research Station (VRRS) and Douglas Daly Research Station (DDRS)
Objectives:
To establish the relationship between body weight (and/or condition) and re-mating conception rates for first calf Brahman heifers in Northern Australia.
To produce a simple chart showing the conception rates that would be expected from mating first calf heifers at different weights.
As the project has just been running for one year, only preliminary data is available at this stage. The project is being conducted at two sites where the relationship between joining weight and fertility will be established for heifers first joined as yearlings at DDRF and as two year olds at VRRS.
VRRS (Kidman Springs) – two year- old joining
In mid 2004, 82 first round weaner heifers (high grade Brahman) were selected, weighed and placed in a paddock to grow away from bulls until their first joining in December 2005. As insufficient weaner heifers were available from the VRRS herd, 35 similar heifers were purchased from a commercial station nearby (Killarney) in September 2004. These heifers were weaned from their dams in September and were specifically chosen for their large weaning weights (average 207 kg; range 179-240 kg) as there were insufficient animals in these weight ranges. The weaning weights of all heifers are summarised in Table 1.
Table 1. Number of heifers in each weaning weight range
Wean wt range (kg) Number of animals 100-139 11 140-179 31 180-219 52 220-260 20 >260 3 Total 117
The heifers were mustered and weighed on 29/9/2004 and 26/4/2005 to allow calculation of dry and wet season growth. Cattle growth at VRRS in 2004-05 was poor with below average rainfall and a late start to the wet season (Table 2).
Table 2. Summary of heifer growth in 2004-05
Dry season growth Wet season growth Total year growth Wt on 26/04/05 (kg) (kg) (kg) (kg) Average -7.9 76.3 71.3 262.0 Max 15.0 96.5 104.0 353.0 Min -38.5 47.0 18.0 192.5
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The heifers will be mustered again around October 2005 when they will be weighed and vaccinated against vibriosis. Bulls will then be introduced for the first time in December 2005 and will be removed the following April.
DDRF yearling joining
On 06/09/04, 110 high grade Brahman weaner heifers were purchased from a commercial property in the Douglas Daly region. In addition, 15 heifers that had been weaned at VRRS at the second round in the previous year (2003 R2) were also included. Weaning weights of the purchased and the 2003 R2 heifers at that time are summarised in Table 3.
Table 3. Heifer weight ranges at September 2004
Weaned Wt range Sep 04 (kg) N 2004 R1 185-199 18 200-219 55 220-239 25 240-259 10 260-279 2 Total 110
2003 R2 200-219 1 220-239 2 240-259 3 260-279 6 280-299 3 Total 15
Heifers were vaccinated with 7 in 1 and Vibrovax. They grazed buffel pasture at a set stocking rate of 1.15 animals/ha and had access to Uramol blocks during the dry season and Phosrite blocks during the wet season.
Bulls were introduced to the heifers on 21/12/04 and were removed on 31/3/05. An ultrasound machine was used to scan the ovaries of the heifers at the end of mating to determine pregnancy. This involves scanning the heifers twice, 10 days apart and looking for the presence of a corpus luteum on the ovaries. It was possible to identify most pregnant heifers at this stage with ultrasound. The animals were pregnancy-tested again two months later to detect any missed pregnancies. The results are presented in Table 4.
The 2004-05 season at DDRF was not conducive to good results from yearling mating as very little rain was received before Christmas. Since joining weight is the major factor effecting heifer fertility, the success of yearling mating depends on largely on getting an early or at least normal start to the wet season. Historical data shows that on average the wet season starts at DDRF (defined as receiving two inches of rain in 10 days) on 2 November. When this occurs, data collected previously shows that heifers will grow 65 kg by the start of January. In 2004 they only grew 49 kg on average over this time.
Studies indicate that 270 kg is the joining weight at which good fertility can be expected. With this in mind it was intended that purchasing weaner heifers at a minimum weight of 200 kg and getting an average break to the season would give a minimum joining weight of 265 kg. However the reduced growth combined with the fact that some heifers were purchased despite being lighter than the cut off weight of 200 kg, resulted in lower than expected joining weights and conception rates (see Tables 4 and 5). Table 5 shows that more than half (65%) of the 2004 R1 heifers were lighter than 270 kg at the start of mating.
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Table 4. Summary of pregnancy testing and ovary scanning (end of mating)
2004 R1 2004 R1 2003 R2 2003 R2 N % N % Pregnant 35 32 14 93 Cycling 19 17 Not cycling 56 51 1 7 Total 110 15
Table 5. Effect of joining weight on fertility
Joining weight range (kg) Weaned 230-249 250-269270-289 290-309 310-329 330-349 350-369 Total 2004 R1 % preg 27 30 26 63 67 32 2004 R1 N 15 57 27 8 3 110
2003 R2 % preg 100 100 100 88 100 93 2003 R2 N 1 3 2 8 1 15
The very high pregnancy rate (93%) of the 2003 R2 weaned heifers indicates that the extra six months in age makes a large difference in conception rates (however it should be noted that there were only 15 heifers in this observation). This will be explored further as more data becomes available in subsequent years.
It should be noted that this is only the first year’s data in a five year study and at this stage the numbers of observations in each weight range are quite low and as a result should be treated with caution. As more results become available in subsequent years it will allow conclusions and predictions to be made with more confidence.
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PROJECT: Industry Initiatives to Improve Heifer Performance in the NT
Project Officers: T. Schatz, A. Bubb and S. Leigo
Location: Commercial stations in the Katherine, Barkly and Alice Springs regions
Objectives:
To establish current levels of fertility in heifers in each region.
To investigate current heifer management practices and why some management strategies are not widely adopted.
To demonstrate best practice heifer management in each region and record the production that can be achieved under these systems.
To prepare a best practice manual for heifer management.
Background:
The research work in this project occurs entirely on commercial properties and decisions about what is studied are made by producers through producer groups such as KPIAC, BRAC, and ASPIAC and managers of the properties where the research work occurs.
Part of the project is to establish what the current levels of fertility are in each region and how heifers are commonly managed. This will be done through a face to face confidential survey of managers as well as performance recording on commercial properties. The performance of heifers will be documented for two years on three properties in each of the three regions.
The main body of research in each region will be demonstrated on a commercial property that is selected by PMG. Management practices that are selected by PMG will be trialled at these sites. This will provide an opportunity for the evaluation of management practices that producers would like tested but do not have the time, resources or research skills to conduct them. The demonstration sites will run for five years.
Progress
Survey
The survey has been conducted and results should be available in next year’s Technical Annual Report as well as in other publications.
Performance recording
In the Katherine region commercial performance recording is under way on Riveren, Killarney and Willeroo. At this stage we only have pre-joining weights recorded.
In the Barkly region commercial performance recording is under way at Benmara. We are still trying to find other properties that are willing to be involved.
At Earldunda we are still trying to find other properties that are willing to be involved.
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Demonstration sites
Katherine region – Newry
The traditional way that heifers have been managed at Newry is to put them in a paddock at weaning and keep them separate from bulls until they are ready for their first joining, usually at around two years of age. Then they are put in the main breeder herd. This is quite a quite a common management system in the region. Supplementation is only considered in “bad” years.
This traditional management system will be compared with one which involves a limited joining period (Nov- April/May) and supplementation of heifers from the dry season prior to their first calf until their second joining.
Within these treatments the effectiveness of one vibriosis vaccination prior to the first joining will be tested. The manufacturer of the vaccine states that one vaccination will give immunity for two years in heifers that are older than 18 months.
Progress
Work is progressing well at Newry. In October 2004, 700 maiden heifers (empty) were tagged with visual and EID tags. Pre-joining weights were recorded and half the heifers received a Vibrovax injection. About 10% of heifers were already pregnant but these were not included in the study. Bulls were introduced to both the control mated and continuously mated groups at this time.
The heifers were mustered again in April when they were weighed and pregnancy tested again. Bulls were removed from the control mated group at this time. The results presented here are only preliminary as it would not have been possible to detect recent pregnancies since the heifers were pregnancy-tested on the same day the bulls were removed. More details will be revealed when animals are pregnancy-tested again in September 2005.
Results:
The results so far emphasise the important effect that joining weight has on fertility. As the joining weight increases, fertility increases (see Table 1). Over all, the average joining weight was 236 kg and the pregnancy rate was 47%. In better seasons or years where there is an early break to the season, the average joining weight and the fertility will be higher.
Table 1. The effect of joining weight on pregnancy rates
Joining weight range Number of heifers Pregnancy (%) (kg) on 01/11/04 on 09/04/05 < 200 28 29 200 – 219 155 30 220 – 239 186 44 240 – 259 109 59 260 - 279 76 63 280 - 299 31 71 > 300 9 89
At this stage it appears that vibriosis vaccination may have improved pregnancy rates by 11% (53%) compared with non-vaccinated heifers (42%). However we need to wait until we have all the data in September and conduct a proper analysis before we can be sure.
The weight gain over the wet season (from 01/11/04 to 09/04/05) ranged from 6 kg to 137 kg with an average weight gain of 86.6 kg. The difference in weight gain between individual heifers is very large and
89 Pastoral somewhat surprising although it was only a small number of heifers that gained less than 60 kg. Table 2 shows how many animals gained weight.
Table 2. Range of growth over the wet season
Amount of weight gained ( kg) Number of heifers 5 – 59 24 60 – 79 182 80 – 99 259 100 – 119 101 >=120 19
Barkly region - Helen Springs
Background:
The research work at Helen Springs is to compare the “current management” system with a “minimal handling” system. The interest in the minimum handling system stems from two main areas:
1. A perceived calf loss problem in heifers, possibly due to mis-mothering at early branding. 2. Good performance is achieved in the channel country from one weaning muster per year (with considerable labour savings) and there is interest to see how such a system would perform on the Barkly.
The comparison between the two management systems will serve two purposes. Stations such as Helen Springs which have quite intensive management systems will be able to see how heifers perform when they are left alone, that is, by how much production is reduced, and how this is balanced by the labour savings. Other stations which currently have a more “hands-off” management style will be able to see the benefits of a more intensive management system.
The current heifer management system at Helen Springs is as follows: Heifer calves (> 150 kg) are weaned and then segregated for one year during which time they get loose mix supplement in the dry season and Phosrite or Kynophos in the wet. In the middle of the next year the heifers are pregnancy-tested and drafted for joining (mostly heifers that were weaned at the first round in the previous year are selected). Selected heifers (mostly around 300 kg) are put in a joining paddock. Bulls are introduced in December and mating is continuous from then on. Next July heifers are pregnancy-tested and non- pregnant animals are culled. Usually around 87% are pregnant and they are then sent to different paddocks according to their stage of pregnancy.
In this research all heifers will have been managed like this up until this stage. Then from here they will be split into two groups. One will continue to be managed in the current way while the other will be the minimum handling group (see below).
The current management system: Heifers start to calve from September with a peak in November/December. Calves are branded in February and put back with their mothers to recover. All calves are weaned in April. Smaller calves are fed pellets.
The following July (this is traditionally done in July but for this trial September/October would be better) heifers are pregnancy-tested for their second calf. Usually there is about 80% pregnancy but only about 65% weaning due to calf losses, possibly from mis-mothering during early branding.
The minimal handling system: From here on the only handling is a muster once a year at which calves are weaned.
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Another aspect that will be researched within the trial is the effectiveness of a vitamin A injection in increasing weaning rate. Vitamin A deficiency has been identified as a cause of substantial calf losses in north Queensland, especially during dry conditions. The past wet season has been very poor at Helen Springs (with only 3 inches of rain received) and so the outlook for the rest of the year is for dry conditions with lower than normal pasture quantity and quality. This would seem to be a good opportunity to test the effectiveness of vitamin A injections.
Progress
Due to drought conditions and a large loss of pasture from wild fires the work at Helen Springs has been deferred for a year. Instead of implementing the trials we are doing some performance-recording and will implement the trials next year.
Alice Springs region – Tieyon
Background:
The demonstration is to compare a control group with continuous mating group of heifers in an Angus herd in Central Australia. Vaccination for vibriosis and vitamin A supplementation will probably be conducted in the two treatment groups.
In general, the two systems are as follows:
Continuous mating: Heifers are weaned and are then continuously run with bulls. This is how heifers are currently managed at Tieyon and on most properties in Central Australia.
Control mating: Heifers are kept separate from bulls until they are about two years old when they are joined for the first time. Young bulls are introduced to the heifers for three months (November, December, and January) and then removed. This occurs for their first two matings, after which they are continuously mated.
Since there are currently not enough paddocks available to keep young heifers in the control mating group separate from bulls until they are two years old, we have devised ways to do this artificially by using pregnancy-testing and possibly use of prostaglandin injections for early pregnant heifers that have conceived at the wrong time. A fencing program was planned to increase the number of paddocks but this has had to be deferred due to the drought.
Progress
Due to drought conditions in the Alice Springs region it was not possible to implement the trials this year. However, in June we tagged (visual and EID), weighed and pregnancy-tested heifers to collect some baseline data and to start quickly if some rain does fall in the near future. Preliminary results from this work are presented below.
Heifers from three-year groups were included in the study. Their ages are listed in the following tables. Table 3 shows the fertility of heifers on their first calf. As we have only weighed them once we do not know what their growth has been like prior to joining. So it is difficult to estimate what their joining weights would have been. We will get a better idea of this in future. To obtain 81% pregnancy in green tag heifers at an average post-joining weight of 324 kg seems to be a good result given the seasonal conditions.
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Table 3. Heifers carrying their first calf
Tag colour Age (approx) > or < 255 kg Number Preg or wet (%) Av. wt (kg) Purple 1 year < 8 0 210 Purple 1.5 years > or = 10 60 300
Green 2 years < 17 29 227 Green 2.5 years > or = 130 81 324
Table 4 shows the fertility of orange tagged (3.5 year-old) heifers. About 61% have just had their second calf (are wet), but of them only 17% are already pregnant with their third calf. Of the dry heifers 74%are pregnant with their second calf and most of them are due to calve shortly.
Table 4. Heifers carrying their second calf
Tag Colour Lact. Status Number Preg (%) Av. wt (kg) Orange Dry 43 74 375 Wet 66 17 329
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Program: Extension and Training
PROJECT: The Barkly Herd Management Course
Project Officer: R. Allan
Location: Helen Springs Station, Eva Downs Station
Objectives:
To provide an introduction to managing a pastoral station in the NT, particularly the Barkly Region to enable head stockpersons to be better prepared to make the transition to station managers.
To provide head stockpersons exposure to varying herd management practices across the Barkly district.
To increase knowledge in pasture species and vegetation in the Barkly district and understanding of nutritional needs of stock.
To enable identification of noxious weed species and to be familiar with beneficial control management practices.
To learn new skills that will enhance property efficiency, profitability and land sustainability.
To provide opportunities for interaction between head stockpersons from various pastoral companies and private family-owned operations, key industry professionals and representatives.
Background:
The Barkly Herd Management Course was developed in 2002 to provide region-specific information to station staff to assist in strengthening and developing their knowledge through expert presentations and industry networking. Courses were conducted in 2002, 2004 and 2005 at stations on the Barkly Tableland.
Developments
Participants representing nine stations attended the 2005 Barkly Herd Management Course which covered beef production, natural resource management, ruminant nutrition, breeding stock selection, weaner management and supplementation strategies.
Presentations were made by representatives from the University of New England, CRC for Beef Quality, S. Kidman & Co., Hetyesbury Beef and DPIFM. Presentations included practical assessments of cattle.
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PROJECT: Barkly Rangeland Management Course
Project Officer: R. Allan
Location: Commercial Stations in the Barkly Region
Objectives:
To provide Barkly pastoralists and their employees a Barkly Rangeland Management Course.
To update and implement courses to improve land management skills of participants.
To stimulate interest of participants in rangeland management and monitoring.
Background:
The project was initiated in response to enthusiastic requests from pastoralists on the Barkly Tableland to develop a training package based on natural resource management for station staff. The Barkly Rangeland Management course started in 1999 and has continued as a series of training days on Barkly pastoral properties.
Developments
A new biodiversity component has been added to course with material prepared by Department of Infrastructure, Planning and Environment.
Attendees included 28 staff from three Barkly pastoral stations.
PROJECT: Katherine Rangeland Management Course
Project Officer: T. Oxley
Location: Commercial Stations in Katherine Region
Objectives:
To develop greater knowledge on stations about land management issues.
To assist pastoral stations to develop commitment and motivation in their staff and thereby increase staff retention.
Background:
The Pastoral Production Division in Katherine developed the one-day Rangeland Management course in 2001 in response to perceived need for better education of station staff about land management issues in the Victoria River District. The courses are conducted on properties and are a forum for knowledge and capacity-building in the cattle industry for pasture health, weed management, fire control and use and infrastructure planning. In recent years many stations in the Victoria River District have experienced high staff turnover which has been attributed to lack of motivation among staff. It was thought that greater training would help to increase knowledge, interest and motivation and lead to greater retention of staff.
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Results:
Rangeland Management courses have been conducted in the last 12 months on the following properties: Tanimbirini; Ruby Plains, where they were joined by participants from five East Kimberly stations; Carlton Hill, where they were joined by participants from Legune Station, Montijini where they were joined by participants from Camfield (this was held in conjunction with the Katherine Regional Stock Course) and for the Northern Land Council held at Kidman Springs.
Feedback from participants has indicated that the course was very well-received. The majority of attendees enjoyed the course and found it informative and relevance to their work. Highlights from the feedback included clear explanation, effective educational techniques, clarity of information and provision of motivation to learn more. Station managers have requested the course be given again in the coming year.
PROJECT: Katherine Regional Stock Course
Project Officers: T. Oxley, A. Trier, K. McCosker, S. Hourigan, G. Scott and M. Perez-Ruiz
Location: Commercial stations in the Katherine region
Objectives:
To provide stock camp station staff with a greater level of understanding of the industry that they are involved in and an appreciation of the need for a professional approach by all members of the industry.
To create an understanding of different roles within the station environment to build a more team- orientated attitude to the day to day activities of station life.
Background:
Following the development of the Rangeland Management course, the Katherine Pastoral Industry Advisory Committee asked for more courses to be available to stock camps to increase their industry awareness.
Stock camps throughout the Victoria River District (both company and private properties) were surveyed. The objective was to identify gaps in knowledge of current stock camps. The rationale was to develop a course that addressed this gap.
Results:
The stock course is now in its third year. The course covers the following topics: animal disease, post mortem techniques, cattle nutrition and reproduction, horse health, the live export market and some regulatory requirements for branding and dipping of stock.
A Katherine region stock course was held at Top Springs for staff at Montejinni and Camfield Stations this year. This was held in conjunction with the Katherine Rangeland Management Course. Both courses were very well received by participants.
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PROJECT: Checklists of Previous Work
Project Officers: C. Allan, A. Bubb and N. MacDonald
Location: Alice Springs, Tennant Creek, Katherine
Objective:
To compile lists and abstracts of previous research carried out by the Department in the last 15 years as a guide for producers and other users of the information, as an audit to ensure that all research is fully written up and results used, and to ensure that conducted research is not forgotten or repeated.
This project is being carried out in all the main pastoral areas of the NT and was selected as a major priority by each of the pastoral industry advisory groups.
Alice Springs - completed and published (Coral Allan)
A list of Pastoral Production projects from the Alice Springs region was collated for the past 15 years from 1990 to 2005. The information contained in the document was recorded from departmental Technical Annual Reports, Technical Bulletins, Technical Reports, Technotes, Agnotes, file notes and the corporate memory of staff.
A total of 38 Pastoral Production projects were identified, consisting of 26 Rangeland Production and 12 Animal Production projects. Departmental publications covering this period from the Pastoral Production groups were also collated and include 12 Technotes, 29 Agnotes, 10 Technical Bulletins and two Technical Reports.
Copies of the report have been distributed to members of the Alice Springs Pastoral Industry Advisory Committee and to the Centralian Land Management Association. It is considered that this report will be a valuable resource not only for the industry but to future researchers to the department.
Barkly region – list complete, abstracts still to be finished (Andrew Bubb)
The Barkly region has had less research than any other region of the NT. It was therefore decided that the list should include research carried out by other agencies. These are mostly related to wildlife, and Parks and Wildlife staff helped in the compilation of the list. As part of this exercise, a complete library of Barkly research reports is being assembled in the Tennant Creek office.
Katherine Region – list completed, abstracts not yet started (Neil MacDonald)
The Katherine region has a longer list of past projects than the other regions. The audit showed that the Katherine office has a good record of writing up research at a scientific level, but there are several examples of research that has been completed without being published in a form suitable for the pastoral industry. Addressing this deficiency is a major future priority.
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PROJECT: Pastoral Industry Survey
Project Officers: T. Oxley, M. Armstrong, P. Hausler, B. Lemcke, A. Bubb and S. Leigo
Location: Stations across the Northern Territory
Objectives:
To document the state of the cattle industry in the Northern Territory, which will better enable government and industry to monitor the performance of research and development over time.
To collect information to better allow the needs of the industry to be addressed by DPIFM and groups such as Industry Advisory Committees and the NT Cattlemen’s Association.
To determine the most effective ways of providing extension information to producers in each region and to initiate or improve communication between DPIFM staff and cattle producers.
To give the industry an up to date picture of management practices to better tailor future directions for research.
Method:
The pastoral industry survey was developed in consultation with industry in 2004. Pastoral Production and Agriculture staff contacted stations in their regions to be surveyed and conducted the surveys with station managers/owners between November 2004 and February 2005.
Results:
Survey data was collated into an Access database. For the Katherine Region 71 surveys were completed, while 40 surveys were completed for the Darwin Region and 40 surveys were completed for the Alice Springs Region. About 40 surveys were completed for the Barkly Region.
Development
Currently survey results are being analysed. A report will be completed for each region and the whole of the Northern Territory. The reports should be completed by the end of December 2005.
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PROJECT: Development of Old Man Plains
Project Officer: P. Saville
Location: Old Man Plains Research Station
Objectives:
To develop Old Man Plains into a research and training facility for the use of DPIFM.
To help provide the pastoral industry in arid areas with sound guidelines to long-term viability while preserving the health and diversity of the rangeland ecosystems.
Background:
In January 2004, 522 km2 of Owen Springs Station were allocated to DPIFM Primary Industries at AZRI. The land extension allocation extended the AZRI boundaries to a total of 557.5km². The land extension is known as Old Man Plains Research Station. This land was allocated as a demonstration site for research and as a training facility. This research facility will help provide the pastoral industry in arid areas with sound guidelines to long term-viability while preserving the health and diversity of the rangeland ecosystems. Research planning and development programs are progressing, with industry consultation an important component of the process.
Current projects
• Demonstration and testing of Remote Telemetry Technology in the arid semi-arid landscape. • Grazing Strategies Partnerships - 4 paddock rotational trial (in conjunction with CLMA and DKCRC). • GRASP pasture growth model collaboration Swiftsynd site constructed in oat grass pasture. • 2000-2002 fire period analysis with three transect pairs monitored on OMP. • Water smart pastoral production trial that plans to combine the best technologies in stock water storage and delivery on pastoral properties. • Sentinel animals for Virology and the national arbovirus monitoring program (NAMP).
Best practice demonstrations
• Monitoring of wildlife that affect pastoralism to develop and demonstrate the benefits of strategic management, that is dog control. • Land condition monitoring. • Active demonstration of the benefits in forage budgeting and rotational rest grazing. • Fire-break maintenance using plough technology. • Road construction maintenance, particularly in fragile areas. • Forage budgeting to estimate percentage of carrying capacity. • Fencing to land type to better protect the more fragile areas and vulnerable plant species. • Water development for stock distribution purposes.
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Developments
• Cleared 40 km for fence line plus extensive repairs to old fences. • Road grading, erosion control, fence line clearing, firebreaks and cleaning, used up to 280 hours of dozer and grader time. • Tanks and troughs were replaced to supply water to the White Point yards before restocking the area. • Water is in the process of being connected to Mulga Dam. • Approximately 7 km of new boundary fence line was erected from the Stuart Highway to White Point bore. • The cross-breeder herd has been scaled down and replaced by Droughtmasters from Kidman Springs.
Training
• Indigenous cattleman's workshop. • Grazing land management workshop. • Beef CRC information day.
Functions
• Meetings with NTCA, ASPIAC and CLMA on Old Man Plains. • Rangeland conference tour.
Visits
Visitors came from all States and Territories, including the University of Sydney and a number from overseas.
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Sub-program: Indigenous Pastoral Program
PROJECT: Indigenous Pastoral Program
Project Officers: A. Trier, T. Freshwater and C. Delacoeur
Location: The Northern and Central Land Council regions
Objectives:
To increase cattle numbers on indigenous land.
To increase indigenous participation in the pastoral industry.
Project duration: Currently in the second half of the third year on an initial three year contract.
Background:
The indigenous pastoral project is a multi-agency approach to increasing participation by Aboriginal people in the pastoral industry of the NT. It was initiated by a memorandum of understanding (MOU) between the Indigenous Land Corporation (ILC), the Northern and Central Land Councils (NLC and CLC) and the DPIFM in February 2003. The ILC part funded four positions, two within DPIFM over a three- year period, and one each within the CLC and NLC, renewable annually over a three-year period to implement the indigenous pastoral project. It was recognised that a multi-agency approach was required in order to address the many issues and factors involved with indigenous enterprise development. This includes areas such as native title legislation, pastoral expertise, infrastructure funding, training and capacity building, and provision of land management and land monitoring ability. The project has been a landmark case of cross-agency cooperation and setting of unified directions.
The main aims of the project are to increase cattle numbers on Aboriginal land and to increase Aboriginal participation in the pastoral workforce. The vision at the inception of the project was to:
Assist Aboriginal landowners implement sustainable pastoral enterprises and increase pastoral production1 from Aboriginal land in the NT.
The key principles on which the project is based on are:
• To achieve sustainable development outcomes and accommodate multiple land use aspirations, but focus on pastoralism. • In the process of planning, development and implementation of any enterprise, there must be approval, participation and commitment by the land owners in accordance with the requirements of the NT Aboriginal Land Rights Act 1976 and where relevant the Native Title Act 1993. • The preferred development model for this program is to foster direct indigenous participation in the management and operation of pastoral enterprises and maximise indigenous employment and training outcomes. • To focus on maximising the coordination of resources from key agencies, business and industry. • To establish key performance measures and criteria aimed at maximising the delivery of benefits to landowners. Performance may include key measures such as employment, income generation, improved land and infrastructure condition or increased numbers of breeders.
1 “Pastoral Production” means production from livestock industries such as cattle, camels or buffalo from pasture, and related enterprises such as fodder production across the NT. The project does not include horticulture, aquaculture, agriculture and alternative and emerging enterprises such as harvesting wild animals or plants. 100 Technical Annual Report 2004-05
The project is currently run by a steering committee. The role of the steering committee as defined in the MOU is to:
1. Set regional objectives for sustainable pastoral enterprises on Aboriginal land. 2. Establish and agree on performance indicators, criteria for assessing proposals, action plans and methods of monitoring and reporting. 3. Assess proposals for regional projects and prioritise and allocate resources for them. 4. Oversee the implementation and monitoring of regional priority projects. 5. Facilitate cooperation and collaboration amongst contributing agencies to help achieve successful projects. 6. Provide coordinated regional reports to the project manager.
The program currently enjoys the support of most of the senior staff of the contributing agencies as it is recognised that the IPP provides a real on the ground solutions to indigenous enterprise development.
Results:
It is estimated that indigenous land in the NT is capable of running an extra 200 000 head of cattle. Additionally there have been estimates of pastoral industry requirements for labour in excess of 300 jobs per annum. In initiating the IPP, it was realised that in order to achieve long-term success, the program should not focus entirely on numbers (of cattle on indigenous land, or people in jobs), as this may divert the attention away from the need to establish long-term solutions. However, substantial success has been achieved to date. This includes:
• An increase in numbers of 15 000 head of cattle on indigenous land. • A further estimated increase of 10 000 head of cattle on currently-developed country. • The development of more country to carry a further 10 000 head in 2005. • The filling of 18 seasonal stock camp positions by Aboriginal people at various locations. • The filling of 25 short-term positions by Aboriginal people in fencing contracts. • The employment of 11 young Aboriginal people in the indigenous pastoral apprentice scheme.
Other achievements have included:
• The Alice Springs indigenous pastoral workshop – a three day program designed to introduce Aboriginal people interested or involved in pastoral development to agency and other staff who can assist them. • Cooperation and resource allocation from external agencies such as DEET, CDU and DEWR in the provision of funding for training. • Access to indigenous communities for the provision of appropriate land management techniques with regard to fire, feral animals and weeds on indigenous land.
Conclusions
The program is in the third year of its initial three-year life cycle, and as such, a number of issues have yet to be addressed. Most urgent is the need to continue the program to provide ongoing support.
In addition to the renewal of the current program, a proposal for additional positions within a variety of areas is being pursued. This includes a full time program manager funded by the ILC and employed through DPIFM. The manager will, through the Land Councils, oversee the day-to-day operations of the program, provide a central point to handle both internal and external enquiries, look for current and emerging gaps and provide solutions.
Additionally, a full time position is to be based in the Alice Springs Region to provide on-the-ground support to existing indigenous enterprises that might not be eligible for support under the current prioritisation process of the IPP. This will ensure greater service delivery to indigenous communities. 101 Pastoral
SERVICE: ANIMAL DISEASE CONTROL
Objectives:
To maintain a capacity to respond to emergency or endemic diseases of significance.
In consultation with industry and with Commonwealth and State/Territory jurisdictions, to put in place a nationally consistent endemic disease control policy and/or develop one rapidly for new diseases.
A capacity to respond to emergency or endemic diseases of significance is a responsibility of State/Territory jurisdictions. In consultation with industry and Commonwealth and State/Territory jurisdictions, a nationally consistent disease control policy is in place or is developed rapidly for new diseases. There is active disease surveillance (also known as targeted surveillance), risk management and a response component.
Current endemic disease control programs include tuberculosis, cattle ticks, Parkhurst resistant cattle ticks and bovine Johne’s disease. National disease reporting, approval of response plans and cost- sharing arrangements are in place for emergency animal diseases. Training, competency assessment and exercises maintain technical and response capacity for emergency animal diseases.
Legislation to underpin industry programs such as livestock identification, quality assurance programs and to provide the necessary powers for disease control are reviewed nationally and locally with industry and government stakeholders. The necessary changes to legislation are done as required.
Compliance activities include registration and audit activities. The Northern Territory is obliged to satisfy nationally-agreed audit standards and compliance activities to support market assurance programs and national risk management strategies.
PROJECT: Disease Surveillance
Project Officers: B. Radunz, Veterinary Officers and Stock Inspectors
Location: NT-Wide
Objectives:
To provide credible disease surveillance information to support the sale of livestock and livestock products.
To investigate the occurrence of diseases in the NT livestock industries.
To participate in national animal health surveillance programs.
Surveillance of the animal population in the NT includes collection, analyses and interpretation of health and disease data, so that it adds to our knowledge of endemic diseases, identifies new diseases, elucidates risk factors for diseases, and allows planning and implementation of ways to control the disease.
Surveillance covers:
The collection of animal health data during disease investigations initiated by the producer (passive/general surveillance).
Planned surveys to target a specific disease (active/targeted surveillance).
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The provision of NT information as part of national programs to enhance Australia's trading status.
The maintenance of a secure and reliable computer system to store and retrieve the data and to communicate results to relevant parties.
Departmental investment in surveillance activities described in this and other projects in this report is around $1.2 million for 2004-05 (excluding external funding). The surveillance activities provide protection for a livestock industry which in 2002-03 was worth over $184 million to the NT.
The activities described below are major components of this project. The diagnostic highlights are an interesting summary of passive surveillance investigations for the period, and as such do not cover all investigations carried out. Surveillance activities are also covered in other reports, such as the bluetongue survey.
Johne's disease zoning
The Committee (now renamed the Animal Health Committee) introduced formal zoning for bovine and ovine Johne's disease (JD) in Australia on 1 August 1999. There are four zones for both bovine JDs: Free, Protected, Control and Residual. The Northern Territory is a Protected Zone for bovine JD.
In order to maintain Protected Zone status, the Northern Territory is required to fulfil objectives set out in the Standard Definitions and Rules for Bovine JD. This involves surveillance activities and an annual report to the Animal Health Committee. The Northern Territory's Protected Zone status was endorsed for another year by the Animal Health Committee on 5 January 2005.
The Northern Territory completed an active surveillance program in 2001 and 2002 on properties that had imported cattle from control zones interstate since 1990. The surveillance involves a test for JD in blood collected from imported cattle and up to 100 in-contact cattle. The surveillance has shown no evidence of JD.
Surveillance for JD was demonstrated to be effective in the first half of 2002. Two house cows, on two different properties, were tested as part of the surveillance on a dairy herd that was being dispersed, were positive for JD. The dairy had imported animals from interstate control zones. A trace forward and testing program from the index herd was conducted. Many properties were put in quarantine. Owners then had to decide either to post-mortem implicated animals and be removed from quarantine, or to test the animals consistent with the Standard Definitions and Rules. Most owners decided to slaughter the trace forward cows and calves. Eleven calves were retained by five owners, which tested negative. At the end of June 2005, no properties were in quarantine.
The national animal health information system (NAHIS)
NAHIS is a surveillance program coordinated by Animal Health Australia and which has input from State, NT and Commonwealth governments. NAHIS provides timely and accurate summary information on Australia’s animal health status to support trade in animal commodities and meet Australia’s international reporting obligations. It also provides information on Australia’s capabilities and activities with regard to animal disease surveillance and control.
A quarterly report is provided to NAHIS on the NT animal health status, specific testing carried out at Berrimah Veterinary Laboratories and significant animal disease events. Similar reports from all the agriculture/primary industry departments, as well as information from AQIS, Northern Australia Quarantine Strategy, the National Arbovirus Monitoring Program, the National Residue Survey, the Commonwealth Department of Family Services and Health, and various national reference laboratories are collated.
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A quarterly report, Animal Health Surveillance Quarterly, is produced and circulated in the NT to various addressees, including livestock industry groups. There is also information about NAHIS on the Animal Health in Australia website at: www.aahc.com.au/nahis/index.htm.
Animal health newsletter
Animal Health News from the Northern Territory is a quarterly publication produced by veterinary laboratory and animal health staff. It started at the beginning of 1996. It is sent to all registered veterinarians in the NT, border towns in WA and Queensland, stock inspectors, NT livestock industry organisations and other interested people both within and outside the department. The articles from laboratory and field staff in southern and northern regions cover topical animal disease events, animal health surveillance news, information from Berrimah Veterinary Laboratories and other items.
Issues 34 to 37 were published in 2004-05. About 200 copies distributed each quarter. The newsletter is also available from the DPIFM website: www.nt.gov.au/dpifm/dpif/pubcat/newsletters/ahnnt.shtml
Passive surveillance
Investigation of disease events in livestock reported by producers achieves two objectives. First, the provision of a diagnostic service by veterinary officers and stock inspectors for sick animals assists producers to treat, prevent and control disease in their animals, and thereby enhances profitability and animal welfare. Secondly, the provision of this service facilitates the documentation of passive surveillance for both exotic and endemic livestock diseases. Information from passive surveillance can be used for market health assurances in trade. The accumulation of knowledge over time regarding endemic disease conditions in livestock also enhances the advice and extension information that is provided to producers.
There is an active extension program on prevention of diseases such as botulism, tick fever and coccidiosis across the Northern Territory. Advice to property owners is provided on request or following a disease investigation.
Advice may be offered over the phone, or a property may be visited to investigate stock history, conduct clinical examinations, perform post mortems and collect samples. Following assessment of a property or after receiving results of laboratory tests, producers are advised of outcomes and control measures are discussed.
Endemic disease
Table 1 shows the number of submissions by region for the July 2004 to June 2005 period. Field veterinary officers and stock inspectors conducted these activities, usually by visiting properties or by providing advice over the phone. This is a crude estimate of activity because a submission can range from a phone call, to examining one animal, to examining and sampling many animals.
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Table 1. Record of activities by staff to support industry during 2004-05
Darwin Katherine Tennant Alice Total Creek Springs P A R P A R P A R P A R Bee - 1 ------1 Bird 1 - - 1 ------2 Buffalo - 6 1 ------7 Camel ------1 - - 1 Cattle 10 2 6 32 64 - 15 24 - 3 15 - 171 Crocodile 2 ------2 Deer ------0 Goat 1 - - 9 ------10 Horse 2 - 16 ------18 Insect 3 1 - 1 4 - 1 8 - - 6 - 24 Pig 5 - - 1 ------5 Poultry 7 - - 2 7 - - 7 - - 19 - 42 Sheep ------0 Total 31 10 6 62 75 - 16 39 - 4 35 - 283 Source: Animal Health Information System P = Passive (general) investigations A = Active (targeted) surveillance activity (includes NTSESP, bluetongue survey, tuberculosis surveillance, tail rot survey, sentinel herd/flock/insect sampling, JD targeted surveillance, Elsey/Florina virus survey) R = Regulatory/movement activity (includes trace forward testing for JD, movement tests)
The 171 cattle activities included 107 submissions from sampling sentinel and survey cattle herds. There were also 33 submissions from sampling sentinel poultry flocks and 24 submissions from insect collections associated with sentinel herds.
Table 2. Comparison of submissions between 2001-02 and 2004-05
Year Total submissions Cattle submissions Cattle submissions excluding active surveillance and regulatory work 2001-02 209 101 Not available 2002-03 262 183 35 2003-04 248 124 29 2004-05 283 171 60
Sampling of trace forward animals from the JD cases in 2002 accounted for a significant number of the regulatory cattle submissions in Table 1.
Diagnostic highlights 2004-05
Iodine deficiency was diagnosed in piglets in a piggery where stale bread was the only source of food. Treatment with iodised salt produced an extraordinary response.
Emergency animal disease (avian influenza or Newcastle Disease) was excluded from an event of unusual mortality in point-of-lay pullets. Heat stress during the early wet season build-up period with high temperature and humidity was considered to be the cause.
Botulism continues to be diagnosed in poultry and other birds in the rural areas and sporadically on cattle stations. Hypophosphotaemia including brittle bone disease continues to be diagnosed sporadically.
Clinical and non-clinical disease due to equine herpes virus and pyrrolozidine alkaloids was again diagnosed in horses in the Katherine area.
105 Pastoral
PROJECT: Emergency Animal Disease Preparedness
Project Officers: K. de Witte and Pastoral Division Staff
Location: NT-Wide
Objectives:
To participate in contingency planning and training for emergency animal disease preparedness.
To ensure that DPIFM staff, relevant organisations and pastoralists have a continuing high level of awareness in relation to emergency diseases and in their role in a response.
The Protect Australian Livestock Campaign is a nationally coordinated awareness project for emergency animal diseases (EAD) that runs year round. The Territory contributed an image for a new extensive cattle industry product. The EAD hotline continues to receive a small number of important calls, most of which are related to avian problems in response to awareness about avian influenza. Fortunately, all test results were negative for emergency animal diseases. Other EAD submissions have been made, mainly of maggots for screwworm fly exclusion.
The NT Operational Response Plan for foot-and-mouth disease (FMD) was progressed to version 4. This plan details how the Territory will respond to a disease outbreak in the context of its limited resources. The plan is a derivative of AUSVETPLAN and contains a number of appendices with prepared documentation, staffing and positioning information for an FMD response, which would be the worst case scenario.
The Rapid Response Team (RRT) is designed to assist jurisdictions during an EAD response. The Territory has three staff members in RRT who participated in Exercise Adventurous Goose in South Australia. Planning for, and participation in, the national avian influenza exercise – Exercise Eleusis in November 2005, has been the main focus for EAD exercises.
An industry liaison officers training course was held in Tennant Creek for 11 livestock representatives. This was the initial course for a national project that will endeavor to train 1000 representatives from all livestock industries in this important control centre role.
As part of the national emergency animal disease preparedness (EADP) training program, two field veterinarians attended veterinary surveillance workshops and were assessed. The NT continues to send veterinary officers for exotic disease courses at the Australian Animal Health Laboratory (AAHL). One officer went to an AAHL laboratory veterinarians’ course. One person trained on the rapid PCR test for avian influenza and another two trained on the FMD ELISA test at AAHL. The EADP competency standards and assessment methods are being incorporated into the Australian Quality Training Framework. This will allow consistent national recognition of qualifications obtained for emergency response management in the animal disease field.
Departmental officers contribute to the technical and policy management of the national program at several levels. The AUSVETPLAN manual revision is a major issue under the management of Animal Health Australia. There are 33 manuals. Current versions are available at http://www.animalhealthaustralia.com.au/.
Contributions were made to the policy and action plans for a livestock standstill, zoning in a disease outbreak, FMD vaccination and free zone surveillance requirements. Australia has commissioned its own FMD vaccine bank arrangements, which have increased the cost to the Territory.
The Australian Veterinary Reserve is a scheme to train privately employed veterinarians for participation in a response. Four veterinarians with connections to the Territory have been selected for training.
106 Technical Annual Report 2004-05
The EAD Response Agreement has been reviewed, particularly in respect to financial matters. Discussions were held to seek changes to reinforce powers under the Stock Diseases Act to deal with an EAD.
Inspections of garbage disposal facilities in towns, remote communities and stations were conducted throughout the Territory by stock inspectors to determine the risk of inadvertent or deliberate swill feeding to pigs. Swill is garbage containing mammalian or poultry protein and it is not allowed to be fed to pigs. The level of awareness was found to be high and few significant problems were encountered. Public vigilance and reporting is appreciated. One incident of swill feeding was investigated and gave a negative result. Further extension efforts have been made, including a postcard mail out to all rural addresses.
PROJECT: Legislation and Compliance
Project Officers: B. Radunz, Project Leaders and Parliamentary Counsel
Location: NT-Wide
Objectives:
To amend stock and meat legislation as required.
To amalgamate various stock legislations into a Stock Act.
To establish a legislation and compliance program.
There are currently five Acts with associated Regulations relating to stock (the Stock Diseases Act, the Stock and Travelling Stock Act, the Brands Act, the Exotic Disease Compensation Act, and the Hormonal Growth Promotants {Stock} Act). The goal is to amalgamate the legislation into a Stock Act and remove outdated and unnecessary legislation.
To prevent the spread of disease, notices are issued by the Minister or the Chief Inspector of Stock to provide the necessary legislative powers to enforce necessary stock movements within the Northern Territory or to import stock into the Territory.
There is a program to audit compliance with the more important regulatory controls. If non-compliance is detected the response may be to initiate a prosecution, issue an infringement notice, or provide education and a warning.
Activities
Progress was made in revising the draft Livestock Bill planned for introduction late in 2005. Due to revised drafting styles a major rewriting of the draft Bill is required.
The Berrimah Veterinary Laboratory received approved status under the Stock Diseases Act. Permitted approved tests that could be conducted for emergency animal diseases in the Northern Territory were declared and gazetted.
Conditions for importing cattle into the Northern Territory were amended to comply with the changed national approach to manage Johne’s disease.
Compensation rates for various cattle classes were reviewed based on market prices; revised rates were declared by the Minister and gazetted.
The list of notifiable was revised following amendments to the national notifiable diseases list which is reviewed at least every two years. The revised list was declared by the Minister and gazetted. The revised
107 Pastoral list was published on the departmental website and all registered veterinary surgeons were advised. It was not necessary to advise cattle producers directly as the changes were not relevant to the cattle industry.
The following notices were gazetted:
G 33: 18 August 2004 – Approval of the veterinary diagnostic laboratory and tests for emergency diseases. G 33: 18 August 2004 - Approval of identification devices. G 39: 29 September 2004 – Revocation of restrictions on entry or importation of stock into the Northern Territory and restrictions on entry or importation of stock into the Northern Territory. G 12: 23 March 2005 – Revocation of determination and determination of compensation for destroyed cattle – (reactors and un-mustered). G 19: 11 May 2005 – Revocation of declaration and declaration of prescribed diseases.
Compliance program
Audits of health certificates and waybills numbered:
Abattoir 0 Export depots 12 Properties 46
Sale yards 60
Ruminant feed ban – 13
Tick conditions - horses 5
There were no cases of non-compliance detected during the audits.
PROJECT: Tuberculosis Freedom Assurance Program
Project Officers: Kevin de Witte, Regional Veterinary Officers and Staff
Location: NT-Wide
Objectives:
To maintain Australia’s internationally-recognised bovine tuberculosis-free area status by continuing to implement a surveillance program that meets OIE standards and by eliminating detected cases of tuberculosis.
To identify post-2006 arrangements and manage their implementation.
The tuberculosis (TB) impending free area declaration in November 1992 was a culmination of years of work by many pastoralists, private veterinarians and departmental staff, with the expenditure of $192 million. The Northern Territory was declared a free area for TB at the end of 1997 and so achieved the goals of the brucellosis and tuberculosis eradication campaign (BTEC). A further $39 million was spent during the period from 1993 to 1997.
A five-year monitoring program, known as the TB freedom assurance program (TFAP), was funded implemented from 1998 to 2002 by State and NT governments, the cattle industry and the Commonwealth government. The national forward estimate for TFAP was $33 million, of which expected expenditure in the NT was $13 million. The main focus was the turn-off of previously exposed cattle. Three TB cases were detected during an investigation in cattle herds in 1998-99. This resulted in de-stocking of two small herds in 108 Technical Annual Report 2004-05 the Darwin region and an eradication testing program in a large herd in the Katherine region. In 2002, TB was detected in two buffalo herds, resulting in removal of all stock.
TFAP 2 will run from 2003 to 2006 with the above objectives and a national budget of $20.1 million. The program has a new Deed with revised Standard Definitions and Rules. Field TB testing will take place, particularly on properties with a TB case after 1988 and where there is little abattoir monitoring due to support for the live export trade. Assistance measures relate to surveillance testing and TB case eradication programs and will phase out during or at the end of the program.
Activities
Eradication
There were no ongoing eradication programs.
TB case detection
No TB cases have been detected in the Territory or Australia since 2002.
National granuloma submission program (NGSP)
TB surveillance at abattoirs has dropped to very low levels in the northern third of the Northern Territory due to the dominance of the live export market. Nationally the program is reaching submission targets. An annual report is available at, http://www.animalhealthaustralia.com.au/aahc/index.cfm?F2232A96-A552-3699-B510- F1205DCA45FB.
During the period 1019 cattle and 136 buffalo were slaughtered at five NT abattoirs. A granuloma detected in a buffalo was not confirmed to be TB. Most Territory cattle are slaughtered interstate and are inspected there. Absence of monitoring at abattoirs of some parts of the feral buffalo herd is an emerging issue for TB freedom monitoring. This has been addressed by TFAP2, funding an additional aerial survey, TB testing of export buffalo and monitoring by three ranger groups in a target area of north west Arnhem Land.
TB monitoring programs
Despite completion of the eradication program (at CF2 or CF3 status), cattle previously exposed to TB- infected animals remain a very low, but possible, risk of undetected TB. Of the estimated 24 million cattle in Australia there were about 200,000 on 70 properties in this risk category in 1997. The national cattle industry decided that owners of these properties should adopt risk management strategies to minimise the risk and scope of a possible TB case in future.
In 1997 there were 50 properties in the NT which records indicated may have had previously exposed to TB stock remaining. The owners of three properties decided not to adopt the voluntary monitor program. Four properties had the majority of exposed cattle (34 000) in 1997 and 1998.
At the end of the 2004-05 year category A cattle decreased to nil. Category B cattle decreased from 35 121 to 25 000, with 21 000 remaining on three properties. Category A cattle are breeders that were 12 months of age or older when exposed to TB-infected stock. Category B cattle are progeny of cattle de-stocked due to TB or progeny of category A breeders. Turn-off at ten years of age is required.
Voluntary monitoring programs have been replaced by approved property TB surveillance agreements, mainly for properties with a history of TB after 1988 which are committed to the live export trade. There are about 60 properties with TB surveillance agreements for TFAP2. It is expected to test about 25 000 annually to the end of 2006.
109 Pastoral
TB testing July 2004 to June 2005
Type Number tested Number of reactors Number with confirmed TB Cattle 21 752 36 0
Testing was done on 18 properties. No buffalo are included.
Post-2006 deliberations are continuing with a mid-program review which was conducted in 2004, reaffirming the success of TFAP2. No definite indication of post-2006 arrangements have been reached but will likely involve TFAP style contingency procedures similar to those currently in place.
Berrimah Veterinary Laboratory successfully passed annual quality assurance testing for TB diagnosis procedures.
Brian Radunz (CVO) was sponsored by TFAP2 to speak on Australia’s TB eradication success at the International Mycobacterium Conference in Dublin.
Expenditure during 2004-05 Operations $175 000* Compensation $21 549 (reactors) Mustering subsidy $238 350 Interest subsidy $0 Freight rebate $0 ∗ Estimate
PROJECT: Transmissible Spongiform Encephalopathy Freedom Assurance Program
Project Officers: B. Radunz, Regional Veterinary Officers and Staff
Location: NT-Wide
Objective:
To maintain Australia’s internationally-recognised freedom from transmissible spongiform encephalopathies by restricted animal material audits, the national transmissible spongiform encephalopathy surveillance program, management of animals imported from Europe, Japan and North America, and aggregation point study.
The national transmissible spongiform encephalopathy surveillance program (NTSESP)
Australia is free of the two major transmissible spongiform encephalopathies (TSE), bovine spongiform encephalopathy (BSE), which affects cattle, and scrapie, which affects sheep. However, the Office International des Epizooties (OIE) Terrestrial Animal Health Code requires that countries claiming to be free of TSE must have a surveillance system in place to detect BSE and scrapie, should they occur. It is important that Australia meets this requirement to assure continued access to export markets. NTSESP was started in 1998 to address this issue. Animal Health Australia coordinates the program, with State/NT/AQIS coordinators organising activities in their regions. There is also information about NTSESP on the Animal Health in Australia website at: www.aahc.com.au/surveillance/ntsesp/index.htm .
OIE guidelines are used to determine necessary surveillance levels. Surveillance involves examining a large range of specimens from cattle over two years of age, or sheep with signs of nervous system disease. The number of cases that each State/Territory needs to examine has been calculated according to the cattle or 110 Technical Annual Report 2004-05 sheep population in each. The calculation was revised in 2004, due to the changes in distribution of cattle and sheep populations in Australia. The NT examines 24 cattle cases annually (and no sheep).
The program operates on the calendar year. The NT achieved 20 submissions from cattle that were negative for BSE in 2004. Government veterinary officers, stock inspectors and a private veterinary practitioner collected samples in the NT. Some of the diagnoses for the sampled animals included bovine ephemeral fever, septicaemia, zamia plant poisoning, transit tetany and pneumonia.
Restricted animal material audits
No non-compliance was detected.
The following audits were done which exceed the minimum number required for the Northern Territory under TSEFAP:
1. One random feed sample. 2. Two export pellet plants. 3. Four reseller audits. 4. Four user audits.
Imported animals
There were 11 animals imported. All are in quarantine and are inspected regularly. Four will be slaughtered in 2005.
Aggregation point study
Twelve samples were collected from 1 January to 30 June 2005. No samples have been collected from aggregation points such as sale yards and export yards. Eleven samples were collected from tuberculin reactors and one sample from a general disease surveillance case.
111 Pastoral
Program: Berrimah Veterinary Laboratories
Objective:
To provide a quality assured veterinary laboratory service.
The Berrimah Veterinary Laboratories (BVL) provide an ongoing diagnostic service in the broad fields of veterinary pathology and veterinary virology. BVL also conducts research projects and participates in quality assurance programs to ensure that the quality of tests carried out at BVL meets national and international standards.
BVL is accredited by the National Association of Testing Authorities in veterinary testing in the disciplines of anatomical pathology (necropsy, histopathology and cytology), microbiology (bacteriology, mycology and virology), parasitology and serology of infection.
A total of 1868 submissions were received and processed during the year at BVL. Each submission may consist of one or more specimens and each specimen may undergo one or more tests in one or more of the 12 Sections of BVL.
The 1868 submissions consisted of 21 046 specimens and had generated 45 031 individual tests in gross and microscopic pathology, bacteriology, clinical pathology, parasitology, serology and virology. The number of tests and reasons for investigation are presented in Table 1.
Table 1. The number of tests conducted at BVL and reasons for tests
Number of tests Reasons for submissions 7650 Diagnosis of disease in production animals, including aquaculture species 71 Monitoring for bovine tuberculosis 2084 Export and movement certification 4279 Diagnosis of disease on a charge for service basis for companion and performance animals, aviary birds and native fauna 25 545 Monitoring of sentinel herds and flocks for exotic and endemic diseases 603 Research programs 4311 Surveillance programs 15 Regulatory 455 Quality assurance
BVL participates in the Australian national quality assurance program (ANQAP) with 23 laboratory tests for inter-laboratory veterinary proficiency testing. BVL also participates in quality assurance programs in bacteriology, haematology, parasitology and anatomical pathology.
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Table 2. Laboratory submissions by region and by species
Darwin Katherine Tennant Alice Interstate/ Total Creek Springs Overseas Amphibian 7 4 1 12 Banteng 2 2 Bat 6 1 1 8 Bee 1 1 Bird (cage and wild) 37 5 2 44 Buffalo 16 1 17 Camel 2 2 Cat 48 3 1 52 Cattle 152 132 40 21 22/1 368 Crab 11 11 Crocodile 20 20 Deer 5 5 Dog 428 49 1/1 479 Dolphin 1 1 Donkey 1 1 Echinoderm 1 1 Fish 85 1 5 91 Goat 22 10 1 0/1 34 Horse 66 25 1 3 95 Human 1 11 12 Insect 71 23 9 8 111 Mouse 8 8 Native fauna 65 1 1 67 Pearl oyster 42 42 Pig 52 2 0/1 55 Poultry 73 15 7 19 1/3 118 Prawn 60 66 126 Rabbit 4 4 Rat 12 12 Sheep 9 9 18 Turtle 5 5 Other/Not 11 1 15/4 31 applicable Total 1,320 273 57 55 137/11 *1,853 * This figure is based on date collected.
Table 3. Type and number of laboratory submissions
Diagnostic 387 TFAP** 41 Export 9 Movement 22 Regulatory 7 Sentinel 261 Research 132 Survey 171 Fee for Service*** 797 Quality Assurance 41 Total ****1868 ** TFAP: tuberculosis freedom assurance program *** Companion and performance animals, aviary birds and native fauna **** This figure is based on date received at BVL
113 Pastoral
Sub-program: Diagnostic Pathology
PROJECT: Diagnostic Pathology
Project Officers: A. Janmaat, J. Humphrey, C. Shilton, L. Melville (25%), S. Benedict, L. Small, R. Wilson, L. Chambers, S. Aumann, C. Burnup (25%), N. Cox, C. Day, and M. Gayoso
Location: Berrimah Veterinary Laboratories (BVL)
Objective:
To provide a quality assured veterinary pathology service to support diagnostic, regulatory and research programs in livestock health and production.
The sub-program is divided into Sections of gross pathology, histopathology, cytology, bacteriology, parasitology, serology, clinical chemistry, haematology and urinalysis - the last three are covered under clinical pathology.
Gross pathology
Submissions 190
The activities of this Section consist of post-mortem examinations of cadavers and gross examination of pieces of organs and tissues from a large range of species. The majority of submissions were from terrestrial production animals and aquaculture species - 36% from each. The rest, which attract a service charge, were from aviary birds, native fauna and companion animals (28% of the total).
• Examination of barramundi from a sea cage farm suggested septicaemia as the cause of death. This was confirmed by the isolation of Streptococcus iniae, a first for the NT.
• Necropsy findings in 13 out of 135 caged layers, which had died suddenly, suggested that the deaths were not due to highly pathogenic avian influenza (AI) virus. Histological examination at BVL and AI exclusion testing at the Australian Animal Health Laboratories confirmed that the AI virus was not involved.
• Examination of stillborn and dying neonate piglets suggested iodine deficiency as a possible cause. Histological examination, exclusion of numerous infectious agents and rapid response to treatment appeared to confirm this diagnosis.
• Post-mortem examination of a 12-week-old dog indicated infectious canine hepatitis, which is rarely seen now. Histological examination confirmed the diagnosis
114 Technical Annual Report 2004-05
Histopathology
Submissions 620
There were only seven submissions of lesions from field reactors or abattoirs under the national granuloma submission program. The brains of 25 cattle were examined as an ongoing NT contribution to the national transmissible spongiform encephalopathy surveillance freedom assurance program. This program is designed to demonstrate freedom from BSE and scrapie, and to provide early detection should these diseases occur. The majority of submissions were for diagnosis of disease in terrestrial production animals (138), aquaculture species (121) and companion animals and native fauna on a charge for service basis (326).
• All submissions for TB and BSE were free from histological evidence of the respective diseases.
• Histological examination of pearl oysters for health certification was a common request.
• Experience in the NT showed that histo-pathological examination alone was inadequate for detecting the viral nervous necrosis virus in barramundi fingerlings destined for translocation.
• Spirorchid egg granulomas were detected in the tissues of an immature turtle from Darwin Harbour.
The Histology Section participates in the histology proficiency testing program of the Australian Animal Pathology Standards Program.
Cytology
Submissions 127
Submissions from private practitioners on a fee for service basis accounted for 71%; submissions for diagnostic purposes from production animals accounted for 20% and surveillance submissions accounted for 9% of the total.
Bacteriology
Submissions 492
Submissions from field TB reactors accounted for 8% of the total, diagnostic submissions for 26%, fee for service submissions for 59% and movement, surveillance and QA submissions for 7%.
• A first for the NT was the isolation of Streptococcus iniae from an outbreak of disease in farmed barramundi.
• Botulism was commonly diagnosed in chickens, ducks and geese which had been submitted for avian influenza exclusion.
• Pseudomonas pseudomallei, the cause of melioidosis, remained a common NT isolate from a variety of species which included captive Sambar deer and an Iguana this year.
• The Bacteriology Section participates in a joint project on the epidemiology of Salmonella ball with the Centre for Disease Control, NT Health and Community Services.
For QA purposes, the Section participates in the IFM proficiency testing program for veterinary microbiology and the three Leptospira MATs and culture of Mycobacterium bovis (the cause of bovine tuberculosis) tests which are part of ANQAP proficiency testing.
115 Pastoral
Parasitology
Submissions 200
Diagnostic submissions accounted for 54% of total submissions; fee for service for 25%, and movement, research, surveillance and QA submissions for 21%.
• Investigations continued into the problem of anthelmintic resistance in goats.
• Interesting parasites from a variety of species included:
- a skin monogenean identified as Capsala sp in striped marlin; - worms pouring out of a pelican’s bill were identified as Contracaecum sp.; - Eimeria mykytowyczi caused severe coccidiosis in a wallaby; - Echidnophaga gallinacea, the stick-fast flea, was found in dogs and a cat from East Arnhem Land.
The section participates in a faecal egg count proficiency testing program run by Agriculture WA.
Serology
Submissions 193
Submissions from sentinel cattle, from cattle used in bluetongue research, a bluetongue survey and interstate submissions requiring bluetongue ELISA testing were the biggest group at 74%, followed by diagnostic submissions at 13%, regulatory, survey and quality assurance submissions at 6%, and export submissions at 4%.
Eight tests were conducted in the Section as part of ANQAP proficiency testing.
Clinical pathology
Clinical chemistry
Submissions 118
Diagnostic submissions comprised 74% of the total followed by surveillance submissions 20% and fee for service 6%.
Haematology
Submissions 131
Diagnostic submissions comprised 59% of the total followed by surveillance and quality assurance submissions at 27% and fee for service at 14%.
The Section participates in the RCPA (Royal College of Pathologists of Australia) haematology quality assurance program.
Urinalysis
Submissions 44
Submissions from private practitioners on a fee for service basis represented 73% and submissions for diagnostic purposes from production animals 27% of the total.
116 Technical Annual Report 2004-05
Sub-program: Virology
PROJECT: Diagnostic Virology
Project Officers: L. Melville, N. Hunt, R. Weir, M. Harmsen, S. Walsh, S. Davis and D. Flanagan
Location: A.L. Rose Virology Laboratory, Berrimah Farm
Objective:
Provide an accurate, efficient and reliable veterinary virology service to support diagnostic, regulatory and research programs in livestock health and production.
Background:
The diagnostic virology service comprises virus isolation and identification, and serology. An increasing number of virus detection tests based on Polymerase Chain Reaction (PCR) have been introduced to supplement conventional isolation techniques.
Results:
During the year 159 submissions were received for diagnostic virus isolation, electron microscopy or PCR including three for export testing. Bovine ephemeral fever (BEF) virus was detected by PCR and isolated from cattle. Bovine herpes virus 2 (BHV2) was isolated from cattle at Beatrice Hill Farm. A total of 189 submissions were received for diagnostic serology, including seven for export testing. A further 49 submissions were received from NAQS and other surveys with 13 submissions from research projects.
An increasing number of samples associated with aquatic animals were received during the year including 220 fish samples for nodavirus PCR; 561 prawns and one crab for GAV PCR; 1666 prawns and 48 crabs for white spot PCR.
Export testing consisted of 671 cattle sera for enzootic bovine leucosis (EBL), 54 cattle blood samples for bluetongue PCR, four horse sera for equine infectious anaemia (EIA) and five horse sera for Hendra virus.
The Australian national quality assurance program provided quality assurance tests for agar gel imunodiffusion tests for EBL, BVD, EIA, BEF, epizootic haemorrhagic disease, bluetongue and Aino. Virus neutralisation tests were performed for IBR, bluetongue, BEF, Akabane and Aino. Haemagglutination inhibition tests were performed for the Newcastle disease virus.
A total of 23 437 serological tests were performed during the year.
117 Pastoral
PROJECT: National Arbovirus Monitoring Program (NAMP)
Project Officers: L. Melville, N. Hunt, M. Harmsen, R. Weir, S. Walsh, D. Flanagan, G. Bellis and S. Davis
Location: BHF, BARC, DDRF, KRS, VRRS, AZRI, Rockhampton Downs, Mt Sanford, Inverway, Alexandria Downs, Muckaty
Objectives:
To support trade by providing information to meet Australian Quarantine and Inspection Service (AQIS) requirements for export protocol negotiation and certification.
To provide bluetongue early warning by the dynamic surveillance of the northern bluetongue endemic area to detect any new viruses or vectors entering Australia and monitoring any southern spread.
To control important insect-borne endemic disease by monitoring for endemic virus activity and insect vectors which transmit these viruses.
Background:
NAMP is an integrated national program jointly funded by industry and governments to monitor the spread of economically important insect borne viruses of livestock and their insect vectors.
Method:
Monitoring is achieved by using sentinel herds at various sites around the Northern Territory, which are bled at regular intervals and tested for antibodies to a number of viruses, Weekly blood collections are made and virus isolations are performed at BHF. Monthly light trap collections of insects are also made at each site.
Results:
1. Sentinel herd serology and virus isolation
Beatrice Hill Farm
A total of 180 viruses were isolated from the following groups:
Bluetongue type 20 Jan - May 57 Bluetongue type 21 May 5 Palyam Bunyip Creek January 1 Simbu Akabane December 3 BEF October 12 EHD type 5 Jan - May 32 EHD type 7 Oct - Feb 32 BHV type 2 April 2 U-ngrouped/un- 36 typed
118 Technical Annual Report 2004-05
Berrimah
Monthly serology indicated the following activity:
Bluetongue October - February Akabane December - January BEF March - April Palyam September, March EHD March - April
Seven bluetongue type 21 isolates were made.
DDRF
Monthly serology indicated the following activity:
Bluetongue April - June Akabane November - December BEF February – June EHD February - April Palyam September, December – January
Three bluetongue type 21, two bluetongue type 20, one EHD5 and two bluetongue group isolates were made.
KRS
Monthly serology indicated the following activity:
Akabane December - January BEF March Bluetongue May - June EHD June Palyam January - February
Two unidentified isolates were made
VRRS
Monthly serology indicated the following activity:
Akabane June Bluetongue September Palyam October
Two bluetongue type 21 isolates were made.
Mt. Sanford
No arbovirus activity was detected.
Inverway
No arbovirus activity was detected.
Muckaty 119 Pastoral
No arbovirus activity was detected.
Rockhampton Downs
No arbovirus activity was detected.
Alexandria Downs
No arbovirus activity was detected.
AZRI
Serology indicated BEF activity in April.
2. Entomology
Trapping with the standard incandescent light identified C. brevitarsis at BHF, Berrimah, DDRF and KRS in most months. The very dry wet season resulted in below normal collections at VRRS. Small numbers were found at Hudson Creek and the Darwin port monitoring site from December to February. This is the first time C. brevitarsis has been identified at this site. Large numbers were also found in a single collection from Newcastle Waters.
C.actoni was found at BHF, Berrimah and KRS. A single insect was collected at Hudson Creek in December.
C. fulvus, C. wadai and C. dumdumi were limited to BHF.
PROJECT: Monitoring for Murray Valley Encephalitis (MVE) and Kunjin Viruses for Medical Entomology
Project Officers: L. Melville, N. Hunt, S. Davis, S. Aumann and N. Cox
Location: Darwin, Katherine, Tennant Creek, Alice Springs, Gove, Jabiru
Objective:
To detect flavivirus (MVE and Kunjin) activity through poultry sentinel flocks which are bled monthly and tested for antibodies to these viruses.
Background:
Sentinel chickens are used to monitor flavivirus activity in Australia. Currently 31 flocks are maintained in the north of Western Australia, nine in the Northern Territory, 10 in New South Wales and 10 in Victoria. The aim is to provide early warning for the potentially fatal disease in humans caused by the viruses MVE and Kunjin.
Results:
Sentinel flocks were located at Leanyer, Howard Springs, Beatrice Hill Farm, Katherine, Tennant Creek, Alice Springs, Ilparpa swamp, Gove and Jabiru. Seroconversions to MVE were widespread, occurring at Howard Springs in June, at Katherine in January, February and June, at Jabiru in April and June, at Tennant Creek in March, at Gove in April and at Beatrice Hill in June.
Seroconversions to Kunjin were more restricted, occurring at Leanyer in August, September and March to May, at Howard Springs in January and May, and at Gove in May.
120 Technical Annual Report 2004-05
PROJECT: Bluetongue Survey
Project Officer: L. Melville
Location: Tennant Creek and Katherine regions
Objective:
To provide scientifically defensible evidence for the location of the bluetongue surveillance zone in the Northern Territory, Queensland and WA.
The 2003 bluetongue surveillance zone for the Northern Territory was proposed by 31/12/2002. The 2004 bluetongue surveillance zone for the Northern Territory was proposed by 31/12/2003. The 2005 bluetongue surveillance zone for the Northern Territory was proposed by 31/12/2004.
Background:
The national arbovirus monitoring program (NAMP) sentinel herds are sparsely distributed in northern Australia and limited serological samples are collected for other purposes. Defining the limits of the free zone is therefore difficult and often based on historical data that may not accurately reflect the two-year monitoring program required by the OIE.
This strategic annual seroprevalence survey for antibodies to bluetongue virus (BTV) in cattle in the Northern Territory, Queensland and the Pilbara region of Western Australia is being carried out with support of Meat and Livestock Australia. The three-year project was completed in December 2004.
Results:
2004 Survey
In 2004 sampling was again carried out along north - south transects, with one property in each of the three bluetongue zones (based on the March 2004 map) to be sampled along each transect.
A total of 1261 samples were tested from 13 properties. For three transects, sampling of the property in the Zone of Possible Activity was not needed because properties further south had positive reactors to bluetongue tests.
Table 1 shows results for 2004. Of the properties that had positive results, six had BTV serotype 1 activity, one had BTV serotype 21 activity and three could not be typed, probably due to low antibody titres.
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Table 1. Results for 2004 – Northern Territory
Property BTV Zone No. tested No. seropositive Seroprevalence (Feb. 2004 map) (ELISA) (95% CI*) 1 Poss. transmission 92 0 0 (0-4.0) 2 Poss. transmission 100 3 3.0 (0.6-8.5) 3 Poss. transmission 100 3 3.0 (0.6-8.5) 4 Surveillance 100 0 0 (0-3.6) 5 Surveillance 91 2 2.0 (0.3-7.7) 6 Surveillance 97 2 2.0 (0.2-7.2) 7 Surveillance 92 1 1.1 (0.03-5.9) 8 Free 100 1 1.0 (0.03-5.5) 9 Free 99 0 0 (0-3.6) 10 Free 96 8 8.3 (3.7-15.8) 11 Free 93 1 1.1 (0.03-5.8) 12 Free 100 0 0 (0-3.6) 13 Free 101 1 1.0 (0.03-5.4) Total 1261 * 95% exact binomial confidence interval
Over the three years of the project 3250 serum samples were tested from 36 locations. Testing detected bluetongue in previously free areas and resulted in a southerly extension of the zone boundaries. The zone boundaries were defined by December each year and incorporated into the national map that was endorsed by Biosecurity Australia. Accurate mapping of the zones has provided confidence in the surveillance, which enables export of livestock to bluetongue-sensitive markets.
PROJECT: Protection of Cattle from NT Vectors of Bluetongue and Bovine Ephemeral Fever Viruses by Covered Pens, Chemical Treatments and Stock Crates
Project Officers: L. Melville, N. Hunt, G. Bellis and M. Hearnden
Location: Beatrice Hill Farm, A.L.Rose Virology Laboratory, Berrimah Farm
Objectives:
To monitor Culicoides and mosquitoes that attack cattle in covered pens and to assess the additional protection provided by treating cattle with an effective insecticide and/or treating pens with insecticide.
To assess the effectiveness of a genuine stock crate in reducing attack by Culicoides vector species and mosquitoes.
To assess the additional protection provided by treating the stock crate and the cattle before loading.
Background:
Culicoides spp are major vectors of viruses of cattle in Australia. In southern Australia the predominant species of significance is C. brevitarsis, but in the coastal areas of the Northern Territory the diversity of vectors is much greater, with a distinct seasonal variation and much higher numbers. For bovine ephemeral fever virus (BEF) mosquitoes are also important vectors.
Previous work in the NT has shown treatment with insecticides could significantly reduce the numbers of Culicoides spp collected on cattle. The most effective chemical trialled was deltamethrin. This work also showed that the number of mosquitoes feeding on cattle could be reduced by chemical treatments. Work in
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Queensland has also shown that holding cattle in pens with walls and a roof significantly reduced numbers of both Culicoides brevitarsis and C. wadai present. Bifenthrin (FMC Chemicals Pty Ltd) has been shown to be effective in reducing midge and mosquito populations when applied to surfaces such as walls or vegetation.
Method:
Portable yard panels were used to construct pens. Each pen was similar in width and height to a standard livestock crate but the length was shortened to facilitate collections and reduce the number of animals used. The pens were constructed with walls made of plywood. The roof was a tarpaulin cover attached to the top of the panels approximately 1800 mm from the ground.
Eight pens were placed side by side, 25 m apart in a north – south alignment. Two pens were used as controls and two pens were allocated to each of three treatments. The treatments were:
• deltamethrin treated cattle, untreated pen; • untreated cattle, bifenthrin treated pen; • deltamethrin treated cattle, bifenthrin treated pen; • untreated cattle, untreated pen (control).
Cattle were randomly allocated to each treatment and the control pens. Yearling cattle were used as bait animals and loaded in the pens at less than the usual transport densities of 0.76 square m per 250 kg animal. Four animals per pen were used. Deltamethrin was applied about eight hours before collections commenced according to the recommendations for buffalo fly. The treatment was reapplied at weekly intervals. Treated cattle were used in the same groups for each replicate to prevent residual chemical effect. Bifenthrin was applied to the relevant pens once before the collections commenced as the effectiveness of the chemical was claimed to be six weeks.
Two cattle transport stock crates were obtained from a commercial operator and located at Beatrice Hill Farm. One stock crate was loaded with untreated cattle. The other was sprayed with Bifenthrin according to the manufacturer’s instructions for protection against heavy insect attack and loaded with deltamethrin treated cattle. Cattle were loaded into the upper and lower decks at less than the normal transport densities of 0.76 square m per 250 kg animal. Six animals per deck were used.
Collections were made using mechanical aspirators. Each collection was of five minutes duration. Two operators made simultaneous collections from animals in a control and a treatment pen. The collections from the remaining treatment groups were made immediately after the first collections. Replicate pens were similarly collected immediately afterwards. Each round of collections was completed within 30 minutes.
Collections were sorted according to Culicoides species and total mosquitoes. Culicoides species were sorted by sex and physiological stage. Data was analysed to test for differences between treatments of those species collected in significant numbers.
Results:
The results the pen trial showed two distinct types of responses by species of Culicoides. The group comprising C. actoni, C. marksi, C. brevitarsis, C. fulvus and C. bundyensis appeared to be reluctant to enter pens. For these species the pen alone provides cattle some level of protection against attack. Conversely, the group comprising C. oxystoma and C.peregrinus was not discouraged by the pens. Mosquitoes were also not discouraged by the pens and may actually be attracted to covered pens.
No additional protection was provided by chemical treatments for the species that were discouraged by the pens. For the species of Culicoides that were not discouraged by the pens, chemical treatments provided a significant reduction in the number of insects collected from cattle. All treatments were effective although mean numbers suggest that treating cattle provides greater protection than only treating the pens. Results
123 Pastoral for mosquitoes suggest that they are attracted to pens but chemical treatments will provide reasonable protection.
Numbers of midges and mosquitoes collected from within the stock crates were always lower than those collected from the control group suggesting that crates alone provide some protection from attack for the species studied. For C. actoni and mosquitoes the protection was greater on the lower deck. The effect of treatments was variable with only mosquitoes showing reduced numbers in treated groups compared with untreated groups on each deck.
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SERVICE: LIVESTOCK MARKET ACCESS
Program: Livestock Market Access
Objectives:
To support the trade of animals and animal products by maintaining internationally and nationally acceptable standards for animal health assurance.
Projects within the Livestock Market Access Service and Animal Disease Control Service complement each other to deliver services to protect and enhance the health and marketability of Northern Territory livestock and livestock products.
Internationally and nationally acceptable standards for animal health assurance must be maintained to support the trade of animals and animal products. The estimated annual turnoff of cattle is between 400 000 and 500 000 annually with only about 5000 slaughtered in Northern territory abattoirs. The remainder (both slaughter and feeder animals) are slaughtered at abattoirs in other States or overseas. About 1000 camels and 2000 buffalo are exported annually. Health and welfare requirements of destination markets must be satisfied.
A key function is to provide health certification for consignments of livestock and livestock products produced in the Northern Territory, so they comply with the requirements of other Australian States and importing countries. Inspection, treatment and certification services are provided to facilitate the sale of animals and animal products. Animals are inspected, treated and certified for domestic markets. Property of origin certificates are provided for NT-bred cattle, camels and buffalo which are exported. Meat and crocodile skins are also exported.
In order to provide credible health certification, the program monitors the disease status of NT livestock by investigating disease incidents and conducting planned surveillance activities. Information is collected on the prevalence, incidence and distribution of bacterial and viral animal diseases, plant toxins and other toxic and deficiency states. Disease investigations, which exclude exotic diseases as a possible diagnosis, provide surveillance data to facilitate trade and may enable advice to be provided on disease control options. Planned surveys may be done to maintain or increase market access.
The Berrimah Veterinary Laboratories (BVL) play an important role in gathering objective information on disease status of NT livestock.
Programs are also in place to satisfy consumer demands for animal products that are free from disease and chemical residues. Such programs also help protect the community from zoonoses (diseases transmitted from animals to humans).
The NT is represented by the Chief Veterinary Officer on the national Animal Health Committee and the national Consultative Committee on Emergency Animal Disease.
The programs depend on a team of professional and dedicated Stock Inspectors, Veterinary Officers and clerical support staff, in close collaboration with BVL staff.
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PROJECT: Animal Health Information System
Project Officers: B. Radunz, R. Wilson, BVL Staff and Veterinary Officers
Location: NT-Wide
Objectives:
To maintain an efficient and reliable database to store animal health and disease information.
To coordinate the NT component of a national animal health information network.
An accurate and reliable mainframe database, called ANDI, is used for storing animal health and disease information. ANDI is used by both laboratory and field animal health staff for storing and retrieving investigation details and test results. Quantitative data from ANDI is used for preparing the NT report to the national animal health information system (NAHIS) and to the national arbovirus monitoring program (NAMP), and any other ad hoc report requests. Significant disease event information is stored on it.
ANDI is used to record and report details and results on all submissions to BVL from a wide variety of clients such as other DPIFM staff in animal production, agriculture and fisheries, private veterinary clinics, livestock exporters and the public.
The Department has identified the need to remove ANDI from the mainframe. In 2002, the then Department of Corporate and Information Services sponsored an initial evaluation to compare the performance of ANDI with that of the Agriculture Western Australia client and resource information system (CRIS), and the implementation of Sample Manager (a laboratory information management system). The purpose was to determine if they would meet business requirements for managing veterinary laboratory testing and field work recording, as currently performed by ANDI. As a result it was considered beneficial to develop functional specifications for ANDI. It was concluded that there was a serious gap between what could be provided by Sample Manager and was being provided by ANDI. Subsequently, an outside provider was contracted to draw up functional specifications for the replacement of ANDI, and to prepare documents for a tender for a replacement of ANDI. This process has not been completed. The next stage of the project is to find a replacement for ANDI. A review continued in 2004 and a final report was provided in May 2005.
The Northern Territory has contributed to a national working party (the national information managers’ technical group) to propose a national approach for an animal health information management system. A flexible approach which will include plant diseases and pests is being considered. It has two components:
• Surveillance, quarantine, control and recovery.
• Resource management program.
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PROJECT: Animal Welfare Monitoring and Policy
Project Officers: K. de Witte and Pastoral Division Staff
Location: NT-Wide
Objective:
To participate in the development and implementation of appropriate national welfare standards for animals.
Departmental officers are primarily responsible for livestock issues under the NT Animal Welfare Act. Veterinary staff represent the Territory Government on animal welfare matters in a variety of forums, including those discussed below.
The animal welfare working group (AWWG) reports to the Animal Health Committee under the Primary Industries Ministerial Council (PIMC). The terms of reference of the group have been expanded from livestock to dealing with all animal welfare issues of national significance. An example of this type of issue has been the campaign for a national ban on the cosmetic tail docking of dogs, when close liaison occurred with the Minister of Local Government who is responsible for the NT Animal Welfare Act. The Territory has supported the ban and regulations are now in place.
A major business of AWWG is the national model code of practice for the welfare of animals. Codes of practice under revision or being drafted include those on pigs, crocodiles, land transport of sheep, land transport of goats, land transport of poultry, ostriches, emu, deer, horses, and destruction or capture, handling and marketing of feral animals. They are at various stages in the process, and some will be available soon. The intention is that these codes will be progressively adopted under the NT Animal Welfare Act. A major issue in the pig code relates to sow stall housing, which is not relevant in the Territory.
Recently, Animal Health Australia coordinated a government industry forum to discuss the evolution of codes into standards for a more uniform approach to animal welfare in Australia as part of the Australian animal welfare strategy. Final agreement on the new expanded arrangements has yet to be reached.
A major issue has been the Keniry live export review. Subsequent to this review, the Commonwealth Department of Agriculture, Fisheries and Forestry (DAFF) managed a comprehensive process that led to the development and implementation of the Australian standards for the export of livestock in early 2005. A revised version was adopted from 1 July 2005. The Australian Quarantine Inspection Service (AQIS) is responsible for supervision of the final export treatment and inspection process.
A revision of the camel code was coordinated by the Territory in 2003. A major change has been a reduction in resting hump height clearance and pen area. A regulation impact statement was prepared and the revised code is seeking final endorsement by PIMC. It is expected that the code will be available in late 2005.
The national consultative committee on animal welfare (NCCAW) which advises the Federal Minister for Agriculture, Fisheries and Forestry who has sole responsibility for live exports, met for the 34th and 35th time in 2004-05. The following issues of relevance to the NT were discussed to achieve a national approach:
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NCCAW position statements These serve as policy guidelines. The position statement on managing unwanted impacts of vertebrate animals was adopted. Topics under discussion include jump racing, injured strays, assessment of traps, electronic collars, importation of dog and cat fur, recreational fishing, aquatic animals, rodeos, circuses, ritual slaughter standards, drought, fire, Tsunami response, dangerous dogs, dog and cat codes and related urban animal issues, puppy exports, caged birds, bush fires, GMO animals, destruction of pest animals and a national code of practice for zoos. This material is available at www.affa.gov.au/docs/animalplanthealth/animal_welfare/nccaw
Australian animal welfare strategy (AAWS) DAFF is funding and coordinating the strategy. There are three goals:
1. To achieve an enhanced national approach to animal welfare.
2. To achieve sustainable improvements in animal welfare.
3. To achieve effective communication, education and training across the whole community to promote an improved understanding of animal welfare.
DAFF advised that recruitment for the AAWS implementation program will be completed during May 2005. The next step is to convene an AAWS steering committee to focus on three activities: documenting existing activities in 25 areas of animal welfare, defining gaps in animal welfare and setting priorities and timeframes. NCCAW is to assume responsibility for reviews of AAWS and monitoring of its implementation. More details are on the DAFF website.
A number of other issues that have some relevance to the Territory were discussed. These include use of electrical devices, the national curriculum for training inspectors, harmonisation of legislation and micro- chipping standards. Concerns are held that the heavy vehicle driver fatigue management program may impact on long distance livestock transport in remote areas. A study is being conducted to validate safe driver practices in remote areas. The results are expected by the end 2005.
The department is represented on the NT Animal Welfare Advisory Committee (NTAWAC) which met for the eleventh and twelfth times. The NTAWAC annual report is available at http://www.dcdsca.nt.gov.au/dcdsca/intranet.nsf/pages/AnimalWelfare. Training of inspectors is an unresolved issue; departmental staff received in-house training.
All reported animal welfare incidents were investigated. Ten significant investigations were undertaken in respect of starving, injured and perishing livestock species. Some of these actions were in relation to drought in Central Australia. Remedial action was undertaken. There were no prosecutions. The department has developed a ‘welfare of extensively managed stock during dry periods” policy in consultation with the pastoral industry to manage the impact of drought on animals. It is available at http://www.primaryindustry.nt.gov.au/servlet/page?_pageid=159&_dad=portal30&_schema=PORTAL30&_ty pe=site&_fsiteid=195&_fid=26214&_fnavbarid=26270&_fnavbarsiteid=195&_fedit=0&_fmode=2&_fdisplaym ode=1&_fcalledfrom=1&_fdisplayurl=.
The department is represented by an expert member on the Charles Darwin University Animal Ethics Committee. The committee scrutinizes all department projects using animals in accordance with the NT Animal Welfare Act.
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PROJECT: Accreditation Program for Australian Veterinarians (APAV)
Project Officer: R. Morton
Location: NT Wide
Objective:
To provide training and accreditation to private veterinarians to enable them to participate in national animal health programs.
APAV is a national program designed to integrate private veterinary practitioners into the national animal health system to maintain Australia’s international standing in animal health service capability. Animal Health Australia manages this program on behalf of members.
The program aims to establish an internationally recognised process for accrediting non-government veterinarians for involvement in government and industry animal disease programs so their skills and knowledge are used effectively.
APAV has two key parts – an “accreditation” process that provides a veterinarian with basic information about Australian animal health services and issues relevant to the role of an accredited veterinarian, and – an “operational” process that provides newly-accredited veterinarians with specific knowledge and skills to enable them to participate in one or more programs requiring the use of accredited veterinarians.
Currently there are eight APAV-accredited veterinarians in the NT, all of whom work in the livestock export industry.
PROJECT: Chemical Residues and Hormonal Growth Promotants
Project Officer: M. Perez-Ruiz
Location: NT-Wide
Objectives:
To provide chemical residue-free animal products to the consumer, and protect and maintain NT meat and milk markets.
To provide an independent, authoritative and scientific advisory service to industry, government, trading partners and the public on chemical residues and contaminants.
To represent the NT on relevant national committees.
NT animal industries do not have a chemical residue problem. Nevertheless, there is a need for ongoing monitoring to ensure the continued absence of residues. Residue monitoring is important for maintaining access to current markets and gaining access to new markets. The functions of the national residue survey (NRS) are continually reviewed as part of a national risk management strategy to maintain market access. An advisory panel for NRS was established in 2003 and had its first meeting in February 2004.
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This program has four components:
1. NRS.
2. Beef organochlorines, organophosphates and synthetic pyrethroids residues.
3. Hormonal growth promotants (HGP) including EUCAS and HGP free system.
4. National antibacterial residue minimisation program.
NRS
NRS is a random sample survey to monitor residues in Australian agricultural food commodities, and has been operating since the 1960s. Since 1996 the requirement for participation in NRS for domestic consumption as well as for the export market has created an additional cost for small industries. There will be one more component to this program (natural toxins) that is currently undergoing assessment to allow for implementation in the near future.
During 2001-002, DPIFM signed an agreement with NRS to follow-up trace-backs greater than the residue action level (RAL), which is usually twice the maximum residue limit (MRL) and take appropriate action. During 2003-04, DAFF proposed to SAFEMEAT that RAL for lead was inappropriate and that it should be reduced to MRL. Given the reasons for lead occurrence in animal tissue, such a change was appropriate and took effect in 2004.
Activities
During 2004-05, 80 samples (13 more than last year) were collected from NT stock, all sourced through abattoirs (no faecal samples were collected on farm this financial year). Eighty samples were analysed (41 cattle, 10 buffalo, seven camel, five game pig, eight farmed pig and nine horse) of which seven were found to have residues (two camel livers, one beef liver, one game pig liver, one horse liver and two buffalo fat). The residues found were mainly cadmium or lead of environmental origin and in one case (buffalo fat) traces of aldrin and dieldrin. There were three samples with violations (two camel livers and one horse liver) but because they were feral animals, no trace-back could be carried out. There were no violations of antimicrobials, organochlorines or organophosphates from NT-sourced stock.
Beef organochlorines, organophosphates and synthetic pyrethroids
The national organochlorine residue management program (NORM) manages organochlorine risks in beef. The program protects domestic consumers and facilitates international market access. NORM has been under intensive review for more than 18 months. It is currently co-funded by States and industry. The beef industry pays well over $1m per annum. This ongoing cost drained beef industry reserves held by NRS, a situation that cannot continue. CCA and ALFA have decided to make NORM a cost- recovering system under which owners will meet the costs of testing and managing their properties’ risk.
Potential changes to NORM will be implemented in January 2006 (NORM III). It was originally planned to implement changes by 1 July 2005. However, more time was needed to sort out differences between State/Territory coordinators, the Commonwealth and MLA.
There are no organochlorine-contaminated properties in the NT, nor are there any NT properties on the extended residue program (ERP) database. There is only one backyard producer with four cows who has a residue management plan in place in the NT.
The main issue regarding tickicides and insecticides for the NT continues to be the interval between the last treatment and slaughter to satisfy MRL in both domestic and export cattle.
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HGP
Many domestic and export markets are sensitive to cattle products derived from animals implanted with HGP. A national program to comply with European Union (EU) import requirements was developed in 1993. This program comprised two components - controls on the use of HGP in the cattle industry, and systems for the recognition of stock which have not been implanted with HGPs. Controls on HGP use are underpinned by the NT Control of Hormonal Growth Promotants (Stock Act).
The EU cattle accreditation scheme (EUCAS) was designed and implemented in 1999-00 in response to European demands for the individual identification and traceability of animals raised for that market. AQIS took the opportunity to then use EUCAS to underpin its HGP-free certification by legislating for individual property accreditation, animal tagging, transaction reporting and vendor declarations attesting to compliance with scheme rules. Provided strict controls are maintained to ensure HGP-treated cattle are kept out of the EU supply chain, the existing HGP control system will eventually become largely redundant, hence the possibility of a progressive dismantling of that system.
The cattle industry has introduced the livestock production assurance (LPA) scheme which is managed by Meat and Livestock Australia (MLA). LPA is a basic quality assurance scheme that underpins the veracity of national vendor declarations (NVD). The LPA scheme requires producers to keep auditable records of purchased cattle and to link those records to the NVD supplied for the cattle when they are sold/purchased. NVDs are widely used when cattle are sold and the use is driven largely by market forces with limited regulatory underpinning in relation to false declarations. The vendor declares whether the cattle have been treated with an HGP on the NVD.
A review of the EUCAS system was conducted by AQIS to audit how State and Territory governments managed the administrative function of the system. This was necessary in the early stages of the scheme due to the large number of properties applying for accreditation. The number of entrants to the scheme has stabilised (currently around 2000 properties) and it was decided that some anomalies revealed by the review can be better managed by a central administration from Canberra. As of February 2005, AQIS has taken over the administration of the system from State and Territory coordinators and audits will be carried out by AUSMEAT, except for the NT and Tasmania.
After the EU Commission’s visit to Australia in March 2005, EUCAS cattle eligibility rules have been amended to allow the purchase of cows/heifers from outside the scheme provided they are identified with NLIS approved tags applied by the vendor and are accompanied by an NVD attesting to HGP freedom. These animals would be shown on the database as ineligible but their progeny will be accepted in the scheme. Approvals must be sought from AQIS and records must be kept for auditing purposes. This component is now covered under the Federal Export Control Act.
Another important outcome of the EU Commission’s visit was that AQIS has made a commitment to the Commission that whenever a property voluntarily relinquishes accreditation, it will not be allowed to reaccredit unless it has been audited. In the same fashion, accreditation is granted to the person making the application and if that person ceases to work for the property, the new owner/manager will have to apply for accreditation.
There are currently eight NT properties that are in EUCAS (three gained accreditation and two relinquished it during 2004-05) and there is interest from more to be accredited.
EUCAS requires the use of national livestock identification scheme (NLIS) permanent devices containing electronic transponders from which individual identifications can be read electronically. Approved devices may be rumen-pellets or ear-tags applied at weaning which then will remain with that animal for life. This system also requires the use of EU vendor declaration (EUVD) forms which as of 1 July 2004 are no longer the responsibility of State authorities. MLA will be in charge of control and distribution of EUVD.
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No EUCAS properties were audited for compliance during 2004-05 in the NT. For HGP users two properties are audited for compliance each year. Both audited properties passed without problems although an incident was reported during one of them. A register of HGP users is maintained in the NT as a requirement of the national HGP control system. During 2004-05, 92 (21 last year) properties in the NT purchased 305 210 doses of HGP for use (against 110 300 the previous financial year). This is an increase of approximately 64% compared with the number of doses purchased in the previous financial year.
South Australia reported three HGP offences from NT cattle last year. Officers investigated the matter and found that the “offenders” had not purchased HGP but had purchased cattle that may have been implanted. A report was submitted to SA authorities along with a recommendation for better identification processes of animals at abattoirs.
Since 2001, use of pink tags bearing the words "HGP Free" was allowed as transaction devices to declare cattle HGP-free. But they were no longer accepted for the purposes of EU markets. Industry requested this system to remain for the purposes of other markets such as Saudi Arabia, the US, Korea and Jordan. AQIS now uses the pink tag together with the appropriately endorsed national vendor declaration as the basis for the non-EU HGP-free certification system.
National antibacterial residues minimisation program (NARM)
NARM is a random national program to monitor antibiotic and antibacterial contaminants. The national program is now targeted to high-risk areas, which excludes the NT.
Targeted antibacterial residues testing (TART)
Another initiative by AFFA is TART minimisation program. This allows AQIS officers in abattoirs to select high-risk animals for sampling for antibiotic residues. The NT represents a very low risk category for these two programs.
PROJECT: Crocodile Farming
Project Officers: V. Simlesa and R. Morton
Location: Darwin and Katherine Regions
Objective:
To provide a regulatory service to crocodile farms in the Northern Territory.
In order to carry out regulatory duties under the Territory Parks and Wildlife Conservation Act on crocodile farms in the NT, two DPIFM officers are appointed as honorary conservation officers. In addition, the veterinary officer is authorised to provide certification under the Commonwealth Export Control Act.
Regulatory duties include:
• Inspection and certification of export shipments. • Collation of monthly reports from all NT crocodile farms for Environment Australia through the Department of Natural Resources, Environment and the Arts. • Conducting regular full audits and/or inventories of all stock on NT crocodile farms to conform to welfare and to the requirements of the Convention of International Trade in Endangered Species of Fauna and Flora (CITES). • Issuing of export/import permits involving farmed crocodile products produced in the NT/or entering the NT.
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• Regular inspection of NT crocodile abattoirs and issuing of health certificates to accompany crocodile skins, as required by importing countries.
A disease investigation service is provided to all NT crocodile farms on request.
Activities
DPIFM is responsible for all regulatory duties associated with the crocodile industry in the NT.
A Rural Industries Research and Development Corporation and QDPI&F joint venture to manufacture pellets as a source of feed for crocodiles is continuing.
The Technical Officer gave crocodile industry talks to a number of schools as part of ongoing educational/extension work.
Statistics included issuing of 58 export movement permits including 47 for export overseas; export of 6166 crocodile (Crocodylus porosus) belly skins overseas; inspection of 47 skin shipments, with the issuance of 24 health certificates. A total of 50 C. porosus belly skins were imported and 467 C. porosus belly skins were sold in the domestic market. A total of 4621 crocodiles were processed yielding 18 859.2 kg of flesh. A total of 9902 live crocodiles were exported interstate.
PROJECT: Honeybee Industry
Project Officers: K. de Witte and V. Simlesa
Location: NT-Wide
Objective:
To provide technical advice, disease investigation and regulatory services to the honeybee industry.
There is concern over the potential introduction of exotic bees and parasitic mites after recent experiences in Australia and New Zealand. The Asian honeybee Apis cerana was detected in Darwin in 1998 and was subsequently eradicated.
The national sentinel hive program (NSHP) was established in 2000 to enhance surveillance of exotic bees and bee parasites. One such parasite is the exotic Varroa mite, which is a natural ectoparasite of the Asian honeybee. The Varroa mite has switched to the European honeybee (Apis mellifera) as a host, and has become a serious pest in the bee world. There are three highly specialised species of Varroa mite, of which V. jacobsoni has the widest distribution and V. destructor poses the greatest threat. The Varroa mite established in New Zealand in 2000, but Australia remains free from it.
NSHP includes both hives and log traps. The European honeybee hives are established at Darwin Port and East Arm Port. The hives are maintained by the Apiary Officer. Monitoring is conducted every three months. A commercially produced pest strip ('Bayvarol strip'), specifically designed for the detection of the Varroa mite is placed in the hive for 24 hours. A sticky board is placed at the bottom of the hive to capture any Varroa mites detected by the Bayvarol strip. Sticky boards are submitted to the Entomology Section after 24 hours for identification of possible mites.
The log traps have been established to monitor the presence of the Asian honeybee. The trap design has been tested and it was found that the hollow palm tree trunk was the most appealing to the Asian honeybee. The traps are designed with a small access hole on the side for bee entry. Each month the log traps are checked and the presence of honeybees is recorded; if any are present, they are sampled. There are five traps established in the Darwin region, one at Darwin Airport, two in the East Arm area and two in the Darwin 133 Pastoral
Port area. One log trap is also established at Gove and one at Groote Eylandt. Pheromone lures are used in the log traps. They are replaced every six weeks. The Asian honeybee’s preference for hollow palm logs and the attraction to the pheromone facilitate its detection.
Cane toads are proving to be a difficult problem for bee keepers. Cane toads will sit beside a hive at night and rapidly decrease bee numbers. Hives that are weak or newly established are prime targets as toads create noise to attract the bees outside the hive to be eaten. Fencing is not working due to large animal movements and artificial lights attract both toads and bees away from the hives.
PROJECT: Livestock Identification
Project Officers: K. Small and A. Kluth
Location: NT-Wide
Objectives:
To ensure that a livestock identification and tracing system operates in the NT which can satisfy nationally-accepted performance standards.
To ensure compliance with the NT Brands Act and Regulations and the Stock Diseases Act and Regulations.
Consumer demand for food safety has highlighted the need for tracing meat products back to the property of origin. The Australian cattle industry aims to stay ahead of its competitors with this important trade issue.
The national livestock identification system (NLIS)
The NT is committed to implementing the mandatory use of radio-frequency identification devices (RFIDs) for property to property movements. Consultations were held with the NT Cattleman’s Association in each of the four regions on the proposed timetable for the implementation of mandatory use of RFIDs. We are confident that the herd-based tracing system which operates in the NT, effectively meets the national performance standards for livestock traceability.
The introduction of mandatory use of RFIDs in the NT will bring it in line with national consistency for livestock tracing systems. Following confirmation of the implementation timetable, a revised NT NLIS implementation plan will be produced.
Waybills
An audit of the waybill system was conducted across the NT. Where deficiencies were detected corrective action was taken. There has been a marked improvement in the completion of waybills following audit. Approximately 870 000 cattle movements were recorded on the waybill database during 2004.
Pastoral property register
A search facility is now available on the department’s website which allows the public to check property identification codes against property names. This information is also supplied to the national NLIS database on a regular basis.
Brands
Processing included 37 three-letter brand applications, 12 distinctive (symbol) brand applications, 18 earmark applications and 27 transfers of brand applications.
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PROJECT: Meat Industries
Project Officer: R. McFarlane
Location: NT-Wide
Objective:
To ensure compliance with national standards and to foster export and domestic markets for all sectors of the NT meat industry.
DPIFM is responsible for regulating the meat industry in the NT, from slaughter through to processing and storage for wholesale.
The Department of Health and Community Services (DHCS) regulates meat retail outlets.
DPIFM licenses and regulates:
• Abattoirs that slaughter all types of animals, including poultry and crocodiles. • Wholesale meat processing, including the manufacture of small goods. • Game meat slaughter. • Game meat processing. • Pet meat slaughter. • Pet meat processing. • Bait meat (slaughter/processing). • Cold stores (domestic meat storage).
DPIFM’s regulatory role for the meat industry in the NT is enabled by the NT Meat Industries Act 1996, the NT Meat Industries Regulations and the following national standards and codes of practice:
• Australian Standard for Hygienic Production of Crocodile Meat for Human Consumption. • Australian Standard for Hygienic Production of Natural Casings Meat for Human Consumption. • Australian Standard for Hygienic Production of Ratite (Emu/Ostrich) Meat for Human Consumption. • Australian Standard for Construction of Premises and Hygienic Production of Poultry Meat for Human Consumption (Second Edition). • Australian Standard for Hygienic Rendering of Animal Products. • Australian Standard for the Hygienic Production and Transportation of Meat and Meat Products for Human Consumption. • Australian Standard for the Hygienic Production of Game Meat for Human Consumption. • Australian Standard for the Hygienic Production of Rabbit Meat for Human Consumption. • Livestock at Slaughtering Establishments Model Code of Practice for the Welfare of Animals.
Standards are non-prescriptive (outcome based) and initiate change from the historical meat industry compliance method of online government inspection to a system of company self regulation via government approved and audited hazard analysis and critical control point (HACCP) based Quality Assurance (QA) programs.
Sectors of meat industry requiring meat inspectors are required to employ their own.
DPIFM’s primary regulatory function is performed by audit, with audit frequency varying according to throughput and compliance history.
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News
There are currently two game meat processing companies operating six licensed game meat field depots in the NT. A wild pig field-harvesting course conducted by DPIFM was completed by 23 participants during May 2005. The number of game meat slaughter licence-holders has increased from 39 in 2003-04) to 105 in 2004-05).
Progress report
Meat industry licences issued:
• Ten abattoir - seven red meat (one export, six domestic) - three crocodile (one export, two domestic) • Eighteen wholesale processors • Sixteen independent processing and packing operations • Two small goods manufacturers • Three cold storage • Three pet meat processors • Nineteen pet meat slaughter • One hundred and five game meat slaughter.
DPIFM issued 713 health certificates between July 2004 and June 2005 for shipments of meat and meat products to East Timor under an exemption to the Export Control Act issued by AQIS.
Meat transport vehicles
DPIFM is responsible for the standard of vehicles used for transporting meat for human consumption in the NT. Thirty vehicles are currently licensed by DPIFM.
Small remote abattoirs
Oenpelli, Kalkaringi and Palumpa abattoirs are all slaughtering small numbers on a regular basis and supplying meat to surrounding Aboriginal communities.
Litchfield abattoir operates two days per week slaughtering locally grown pigs for the local market and also offers a service kill.
Wamboden abattoir in Alice Springs was recently re-commissioned and operates fortnightly slaughtering camels and cattle.
Ingham’s poultry abattoir announced its closure in March 2004. It is now licensed as a cold store and is expanding to accommodate the extra storage that is required.
Barkly Meats Tennant Creek abattoir, Teys Brothers Katherine abattoir and Batchelor abattoir have not opened for a 2005 slaughter season. Talks are currently being held for the lease/sale of Batchelor abattoir.
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PROJECT: Monitoring and Eradication of Cattle Tick Strains which are Resistant to Chemicals
Project Officers: K. Small, D. Russell and I. Doddrell
Location: NT-Wide
Objectives:
To locate chemically resistant strains of cattle tick on NT properties and prevent their spread.
To advise industry on chemical control of any detected resistant cattle tick strains.
Prior to April 1999 there were no known cattle tick strains resistant to synthetic pyrethroids or amitraz in the NT. Previously some resistant strains to organic phosphates were detected during the 1970s and 1980s. Organic phosphates were banned as an acaricide in 1987.
There are strains of cattle ticks that are resistant to one or more acaricides in Queensland. All cattle from the tick-infected areas of Queensland require a clean inspection followed by a plunge dip to enter the NT. Despite this control, there is a low level of activity to monitor for resistant ticks as there may be illegal movements or inspectors in Queensland may not detect ticks. Although there is little cattle tick control in the NT to improve production, the widespread establishment of resistant ticks would have a significant effect on achieving tick-free cattle for export overseas and interstate.
Fully engorged female cattle ticks are collected in the field and sent to the Animal Research Institute at QDPIF for processing and larval packet testing against a number of tickicides. Collectors and station owners/managers are given the results and appropriately advised. The program targets properties that report poor tick kill and properties on which pour-on synthetic pyrethroids are used for cattle tick or buffalo fly control.
Parkhurst strain resistant ticks (resistant to synthetic pyrethroids e.g. cypermethrin and flumethrin as in Bayticol, Barricade 'S' and Blockade-S) were found on two properties in the Mary River area in April 1999.
Parkhurst strain cattle ticks have been eradicated from one property. There are nine properties infected with Parkhurst ticks. One property also has Biarra strain ticks. Movement controls are in place to reduce the threat of further spread of ticks.
There was no evidence of further spread of resistant ticks during the year.
The establishment of plunge dips charged with amitraz at the Darwin export yard and the Noonamah export yard has facilitated the movement of cattle from infected properties to export under a permit system. There are also amitraz plunge dips at Opium Creek and Twin Hills.
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PROJECT: Stock Movements
Project Officers: Veterinary Officers and Regional Stock Inspectors
Location: NT-Wide
Objectives:
To provide property and animal certification for export interstate and intrastate.
To facilitate interstate and intrastate movements from the tick-infected and tick-protected areas by inspection and/or treatment of cattle and horses for cattle ticks.
To prevent entry of cattle ticks from interstate, particularly acaricide resistant strains from Queensland.
To prevent the entry of Johne’s disease and tuberculosis from interstate.
In consultation with industry and consumers, the NT Government prescribes controls to prevent the spread of animal disease. This was a response to cattle disease plagues common in the 18th and 19th centuries. In recent years there has been increasing industry self-regulation. While market and quality assurance programs have been developed and will continue, there are industry and consumer expectations for governments to protect consumers from health risks and animals from the spread of diseases. This applies within the NT (e.g. for cattle ticks) and for national and international markets (e.g. for bovine tuberculosis and other diseases).
A service is provided to NT producers to facilitate trade by the certification, inspection and treatment of stock, if required. Control programs (e.g. for cattle ticks) may also be implemented. Mobile spray plants and chemicals are provided for spraying horses for movement.
There is continual review of stock movement controls and area declarations in consultation with State governments and industry associations.
Animals from the tick infected area require a clean treatment (clean inspection and treatment) to pass into or through the NT tick-free areas or into the tick-free areas of other States. Treatment is by plunge dipping, except for led and tractable horses and show cattle, which may be sprayed instead of dipping. The tick-free areas in the NT are designated as the Free Zone Protected Area, and the Central Control Zone Protected Area. The tick infected areas are designated the Infected Zone Protected Area and the Northern Control Zone Protected Area. A map showing these areas can be accessed from the following DPIFM internet page: http://www.nt.gov.au/dbird/dpif/animals/cattle_ticks.shtml
Cattle moving to Western Australia also require inspection for burrs.
Cattle moving to all States except New South Wales and South Australia require a health certificate. Cattle moving to New South Wales require a NSW travelling stock statement. Other stock moving interstate may also require a health certificate.
Certifications are provided to the Australian Quarantine and Inspection Service (AQIS) regarding the disease status of properties and animals to satisfy export protocols. The Animal Health Information System is an associated project for improving the reporting and retrieval of disease data. Planned active surveillance programs complement passive surveillance disease monitoring. A total of 290 property of origin health certifications were provided for the export of cattle from NT properties.
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Some export protocols require treatment of animals prior to export. Departmental staff provide this service if authorised private veterinarians are not available. None were provided during 2004-05.
Table 1. Summary of activity for 2004-05
Cattle inspected and treated for cattle tick from tick areas Number of visits 281 Number of animals 92 601 Cattle moved interstate from tick free areas Number of certificates 578 Number of animals 160 849 Cattle inspected for movement to WA Number of visits 41 Number of animals 13 718 Horses inspected and treated for cattle tick from tick areas Number of visits 204 Number of animals 1559 Other stock inspected Number of visits 5 Number of animals 44 Total property visits 531 Cattle inspected at sale yards Number of visits 88 Number of animals 41 467
There were 205 204 NT-bred cattle exported from the port of Darwin during 2004.
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SERVICE: RESEARCH FARMS
Program: Research Farms
PROJECT: Research Farms
Project Officers: Research Farm Managers and Staff
Location: Darwin, Katherine and Alice Springs
Objective:
To provide research farm facilities for government and industry to deliver research, development and extension programs to the primary industry sector.
There are seven research farms in the NT that support Pastoral Division projects to serve the pastoral and agricultural industries. Research farms are essential for the implementation of the department’s research, development and extension programs. While most work carried out on the farms is research- oriented, some operational funding is derived from the sale of livestock and field crops.
As each research farm represents a different region in the NT, they are currently being used as demonstration sites for the introduction and testing of electronic identification systems for cattle. Producers will gain information about the performance of these systems. Electronic identification of cattle will be compulsory in the NT in 2007.
Berrimah Farm (BF)
BF is the headquarters for Primary Industries, DPIFM. It is a research farm covering an area of approximately 200 hectares. It includes an orchard, grazing paddocks, shade houses, a quarantine nursery, an agroforestry plot and sheds for farm and heavy equipment. BF houses the veterinary, fisheries, horticulture, seeds, post-harvest, chemistry and water quality laboratories. The laboratories facilitate the provision of specialist services to industry and support the work of staff.
Project highlights
• Hay production – 154 tonnes of good quality pangola hay was produced from 17ha at 9 tonnes/ ha. The hay is used at VRRS, Old Man Plains and BF. • Provision of grazing and other facilities to sentinel animals for virology and the national arbovirus monitoring program. • Provision of grazing facilities for the buffalo project. • Provision of a base and workshop facilities for the transport of heavy machinery to and from all research farms. • Provision of assistance with the introduction and use of the national livestock identification scheme in the NT. • Replacement of gamba with Strickland grass. This is the first project to replace all gamba pastures on BF.
Beatrice Hill Farm (BHF)
BHF is a 2600-hectare property located 60 km from Darwin, on the Arnhem highway. The farm was established in the late 1950s and is used primarily to support buffalo research. Because BHF is adjacent to
140 Technical Annual Report 2004-05 the Adelaide River, approximately 80% is floodplain. Very high pasture productivity is achieved during the dry season using ponded paddocks.
Project highlights
• Buffalo projects attempt to increase and quantify the genetic benefits of Riverine buffalo through pure- breeding and backcrossing with Swamp buffalo. The performance of intermediate crosses is monitored to evaluate superior genetic make-up for both meat and dairy production in the Top End. • The TenderBuff project provides an alternative market to export, with a stable income for farmers. Crossbred animals are assessed for carcass quality through this project. Pasture ponding provides grazing for turnoff during the dry season. • The farm buffalo herd is also used in an RIRDC project to improve synchronisation for artificial insemination in buffalo. • A sentinel cattle herd is run on the farm for virology studies for the national arbovirus monitoring program. • BHF produced 175 tonnes of grass hay from 25 ha (7 tonnes/ha). The hay is used as supplementary feed at BHF. About 50 tonnes was sent to Old Man Plains for drought feeding. • Repairs were made to the earth banks of the three ponded-pasture areas following blowouts the previous season. • Two paddocks of gamba grass were replaced with Strickland grass. All gamba paddocks will be sown with other species during the next few years. • Fencing started on a recently acquired 100-ha block of land between Middle Point village and CPRS.
Katherine Research Station (KRS)
Located on the outskirts of Katherine, KRS comprises 1240 hectares and is the headquarters for DPIFM in the Katherine Region. KRS staff maintain centre pivot, lateral move and trickle irrigation systems, a dedicated horticulture research area and improved pasture for beef cattle production. Underground water usage is monitored as part of the irrigation program. A further 2000 hectares has been agisted from the owners of the adjacent Old Kumbidgee Station where 300 breeders are run to produce crossbred Tuli, Belmont Red and Senepol females for breeder genotype comparison projects at VRRS.
Project highlights
• Cotton CRC funded research. This is the last year of the 10-year research program. Cotton picking is due to start at the end of August.
Entomology
• IPM trial. Testing the effectiveness of lab-lab, pigeon peas and sweet potatoes as companion crops in an IPM system. • Late season sucking pest trial. Establish sucking pest thresholds post-squaring in cotton. • Companion requirements trial. Assess which crops produce enough Helicoverpa moths to aid in resistance management. • Pheromone trap monitoring trial. Monitor local populations of Helicoverpa armigera, Helicoverpa punctigera, Pink boll worm and Spodoptera litura.
Sesame
• Breed new cultivars and monitor seed quality in different varieties • Entomology studies in sesame • Breeder seed multiplication
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Cattle
• Monitor mature weight and productivity of Belmont Red and Tuli crossbred cattle. • Monitor the relative mature size of young Charolais x Brahman and Brahman cattle in a feed lot. • The annual Farm and Garden Day was held in April where about 1900 people attended.
Victoria River Research Station (VRRS) Kidman Springs
VRRS is located in the Victoria River District (VRD) and is approximately 314 km2 in area. VRRS manages a breeding operation where most progeny are transported to DDRF after weaning. Currently 1100 breeders are stocked at VRRS.
Projects highlights
• Native pasture management. The use of fire in the VRD to control woody vegetation. • Grazing Management. Pasture sustainability. • Herd Management. Improved breeder herd profitability, strategic bull removal, understanding and improving heifer fertility. • Future Markets. Breeding herd efficiency of adult Charolais × Brahman and Brahman multi-breed crossbreeds. • A major producer field day was held at the Station in August 2004. • A power generator was installed at the Station during the year. • A new pump and motor were installed at the main water bore.
Douglas Daly Research Farm (DDRF)
DDRF is a 3100-hectare farm located 220 km southwest of Darwin in the Douglas Daly Region (DDR) with approximately 2000 hectares of improved pasture. Beef cattle production is the main focus for research; however, the farm has 40 hectares of centre pivot irrigation for irrigated peanut and fodder research. The farm also carries out trials on suitable dry-land field crops. DDRF has a primary school, a social club and 35 residents is the hub of a small mixed farming community.
DDRF received 984 mm of rain in the 2004-05 wet season (average 1208 mm) with the first substantial fall on 6 November and the last on 9 March. It was a good season for growing pastures and crops; however, low soil moisture lowered pasture quality quite early in the dry season.
Project highlights
• Improved pasture species evaluation trial. Legume sustainability, leucaena consumption and toxicity. • Weed management trials strategy. Bay 11 long term weeds, pre wet season herbicide management in Cavalcade. • Agriculture and irrigation development. Peanut research, irrigated forage research. • Beef cattle research. Top End multi-breed composite project: Implications of the timing of the break in the season on the management of heifers in the DDR of the NT. • Cavalcade Hay Production. Zero till vs. conventional till. • Grain sorghum variety trials. • Sucker re-growth control trials on and off farm. • Bulk dry-land crop production: - 80 ha sesame - 70 ha grain sorghum - 35 ha Cavalcade hay production - 30 ha leucaena.
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SERVICE: TECHNICAL SERVICES - LIVESTOCK EXPORTS
PROGRAM: Technical Services
SUB-PROGRAM: Livestock Exports
PROJECT: Negros Occidental Cattle Development Project
Project Officer: D. Ffoulkes
Location: Negros Occidental, the Philippines
Objective:
To conduct a joint cattle industry development project with the Philippines Department of Agriculture
Background:
Sustainable development of the NT’s live cattle trade with the Philippines was assisted by the provision of technical assistance and training to establish a cattle industry development project in the Province of Negros Occidental by November 2004 which would help to alleviate rural poverty and diversify the existing sugarcane industry. The cattle program, which is a joint venture between an Australian consortium and the provincial government, aims eventually to import 10 000 head of young Brahman cattle per year from northern Australia.
Method:
An initial study was undertaken to develop a two-staged production system and standard operational procedures for growing out weaners and finishing them in feedlots (Ffoulkes 2002). A trial shipment of feeder cattle from the NT will be used to test the feedlot operation and the markets. A second shipment of young cattle will be distributed to small holder farmers for growing out prior to finishing in small commercial feedlots. Officers from DPIFM will provide technical support and training during the implementation of the project and training scholarships will also be offered to local livestock advisers.
Results:
The first shipment of mostly Brahman crossbred cattle from NT arrived on 1 October 2003 and after 50 days in the feedlot, average growth rates ranged from 0.74-1.02 kg/day for groups of 25 animals taken at random from each of four sheds and body condition scores had significantly improved since arrival. By 75 days, finished cattle could not meet market demand for beef in the lead up to the Christmas period because of limited capacity at the Victorias abattoir. Some live animals were sold to local markets after this period to complete the operation.
In a separate on-farm trial, a group of 20 feeders were lot-fed by a local cattle grower using a mixture of Napier grass and sugarcane tops, brewers spent grains, concentrate feed and molasses. An evaluation of this operation is presented in Table 1. The data showed a reasonable level of productivity in the cattle in terms of growth rate and dry matter feed intake; however, the financial analysis indicated a relatively small profit as a result of low prices for live animals at the local market compared with processed carcasses in
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Manila. The importation and growing out of young cattle prior to lot-feeding for less than the purchase price of feeders is likely to have been more profitable.
Support for a second shipment of cattle depends on developing niche or export markets. Australian cattle prices continue to rise as a result of demand for Australian beef from Japan and because of a stronger Australian dollar. Proponents of the project are looking at producing organic beef to meet a growing demand in Manila and overseas, particularly in the Japanese market.
In September 2004, the officers from DPIFM visited Negros Occidental to encourage project continuity among cattlemen and investors and to offer ongoing technical support. In February 2005, a technical workshop/seminar on requirements for receiving and raising imported Australian cattle was held for the newly-formed Island Cattlemen’s Association of Negros (ICAN) and audits of feed availability and facilities were conducted of member farms. The manager of Sagay City dairy was nominated to attend a two-week farm managers’ work experience program in the NT.
A feasibility study on a proposed fattening operation in neighbouring Negros Oriental province using imported Brahman crossbred cattle was undertaken in February 2005. It was recommended that this operation share a shipment of cattle with ICAN to trial a feedlot operation. It is anticipated that a series of shipments of NT cattle will commence in mid-2005 and the project will be reviewed in December 2005.
Table 1. Evaluation of an on-farm feedlot operation with 20 imported feeder cattle
Measurements Per head Productivity: Initial live weight (LW) (kg) 299 Final LW (kg) 461 LW gain (kg) 162 Days on feed 142 Average daily gain (kg) 1.14 Feed: Estimated dry matter intake (DMI) (kg/d)1 Roughage (25%) 5.56 Spent grain (18%) 4.31 Concentrate feed (90%) 1.80 Molasses (75%) 0.90 Total 12.57 Feed conversion ration (DMI/ADG) 11 Consumption index (DMI as %LW) 3.0 Profitability: Operational costs (A$) Feed (per day) 0.90 Labour (per day) 0.59 Production costs (A$/kg LW gain) 1.30 Purchase cost @ USD 1.35/kg LW (A$ 2) 545 Sales @ PHP 73/kg LW A$ 3 783 Operating costs over feeding period (A$) 211 Net returns (A$) 27 Benefit/cost ratio 4% Source: Raw data from Vicente Hulleza 2004 (pers. com.) 1. Bracketed values are estimated DM content of feedstuffs 2. AUD 1.00=USD 0.74 (rates at 15/08/05) 3. AUD 1.00=PHP 43 (average rates from 15/12/03-15/03/04)
144 Technical Annual Report 2004-05
PROJECT: Cattle Industry Development Project with the Sabah Government
Project Officer: D. Ffoulkes
Location: Sabah, Malaysia
Objective:
To undertake a cattle industry development project with the Sabah Government Department of Veterinary Services (DVS) and Animal Industry.
Background:
The Sabah Government plans for 30% self-sufficiency in beef production by 2010 through sustainable development of its cattle industry using oil palm, accreditation with foot and mouth disease-free status and the establishment of an export market and meat technology centre. This will lead to resumption of cattle imports from northern Australia.
Following a visit by the Minister in September 2004 and the completion of a collaborative program to improve the cattle industry in Sabah through appropriate technology transfer and training, a memorandum of cooperation between DPIFM and the Sabah Department of Veterinary Services and Animal Industries was signed in Darwin in February 2005 by the respective Ministers to develop the cattle industry and trade.
Method:
A working group of representatives from each region will develop action plans and review cooperative activities on an annual basis. Activities in support of industry development and trade between the NT and Sabah include livestock and livestock services, education and training in tropical beef production, facilitation of government processes for participation in trade and investment opportunities and exchange visits by government and the private sector to strengthen ties and identify and develop opportunities for economic development.
Results:
The activities that were identified by the working group for 2005 were: (a) evaluation of management of Sabah government farm; (b) a work experience program in the NT for farm managers and laboratory staff; (c) training in feedlot management; (d) development of training programs for the Sabah Meat Technology Centre; and (e) development of a QA system for the Sabah Animal Disease Research Centre.
Government farm assessments
Two officers from DPIFM visited seven farms and were pleased with the progress achieved since a previous visit in 2004 to improve herd management and productivity. High stocking rates and culling of unproductive stock were still the main issues that needed to be addressed. Nevertheless, a small shipment of imported cattle and buffalo planned for later in the year should maintain their condition on government farms prior to distribution to farmers.
The remaining activities are scheduled for the second part of the year and the program will be reviewed by December 2005.
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PROJECT: Cattle Industry Development in Eastern Indonesia
Project Officer: D. Ffoulkes
Location: Eastern Indonesia
Objective:
To assist with the development of the cattle industry in Eastern Indonesia.
Background:
In June 2004, a workshop on opportunities for cooperation was held at the Assessment Institute of Agricultural Technology (BPTP-NTT) near Kupang. Participants included an officer from DPIFM (also representing Charles Darwin University), staff from the Animal Husbandry Faculty of University of Nusa Cendana (Kupang) and BPTP-NTT scientists and extension officers. Workshop participants pointed out that domestic beef cattle exports from Eastern Indonesia had fallen dramatically over the past decade and they identified better cattle breeder management as the key to regain market supply.
Method:
An ACIAR funded project proposal will be developed and implemented for an integrated and sustainable beef cattle development program in Eastern Indonesia.
Results:
A matrix of collaborative activities was proposed in a submission to ACIAR. The main outputs of the proposal that have been accepted are:
• Demonstrating technology packages for cattle management. • Strengthening of agribusiness skills of cattle producers • Basing cattle industry development on geographical information systems. • Transferring education and technology.
A full proposal is being developed.
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PROJECT: Joint DPIFM/CDU Beef Production Program
Project Officer: D. Ffoulkes
Location: Charles Darwin University and the Rural College, Katherine
Objective:
To establish Charles Darwin University's School of Science and Primary Industries, in collaboration with DPIFM's Primary Industries, as a leader in research and education in tropical and arid beef cattle production.
Background:
Under the NT Government /Charles Darwin University (CDU) partnership agreement signed in 2003, DPIFM and CDU have agreed to work together to establish higher education and research programs at the University’s School of Science and Primary Industries. Arrangements have been made for a DPIFM officer to manage this program for a period of two years.
Method:
The joint program will focus on the following outputs:
• Development and delivery of a post-graduate unit in tropical beef production. • Delivery of short courses in tropical beef production to train international students. • Development of an externally-funded international project (see Cattle Industry Development in Eastern Indonesia).
Results:
International training courses
In December 2004, a 12-day course on Administration and Management of Cattle Enterprises was held at CDU’s Rural College near Katherine for 12 officers from the Indonesian Government Directorate General Livestock Services. The course was organised and presented by DPIFM officers with assistance from staff of the Rural College and included field trips to Douglas Daly and Katherine Research Farms, the AustAsia Depot and Mataranka Station. An outcome of this course was the recommendation that a team of experts from DPIFM and CDU visit Indonesia’s national AI centre to discuss a cooperative program on institutional strengthening. This project is being supported with funding from the Commonwealth Government.
Tropical beef production unit
An application to develop a post-graduate unit on An Introduction to Tropical Beef Production was submitted to the University Panel in April 2005 for delivery in Semester 1, 2006.
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SERVICE: WATER MICROBIOLOGY
Program: Water Microbiology
Sub-program: Water Microbiology Laboratories
Objective:
To conduct bacteriological analysis of water for government departments, the private sector and the general public.
The DPIFM Water Microbiology Laboratories (WML) provide a testing service for numerous types of water including potable water, waste water, recreational water, bottled water, food processing water and dialysis water. WML provides advice and assistance with water quality monitoring, water sample collection, water sample transport logistics and the rectification of water quality problems including disinfection of potable water. WML also functions as a referral service for water quality issues directing enquiries to the appropriate government or private agencies.
WML has a large client base. All analytical services provided by WML are on a fee for service basis. WML is currently preparing to obtain accreditation by the National Association of Testing Authorities, for biological testing.
WML has two laboratories:
The Darwin water microbiology laboratory
The Darwin laboratory is located in the Berrimah Veterinary Laboratories and services the Northern Region of the NT. The following samples were analysed:
Total samples 6175 PWC all samples: 3218 NT Government: 1180 Sewage (all): 340 Submissions: 1946 Tests: 21 612
Submissions increased by 2.6% and samples increased by 2.7% (which is less than the normal annual increase). The largest increase in samples came from NT Health and Community Services as a result of more rigorous testing of dialysis equipment. There were no major new clients.
Current Darwin staff consists of:
Greg Paterson Mila Mahoney Kiki Dethmers (part-time)
148 Technical Annual Report 2004-05
The Alice Springs water microbiology laboratory
The Alice Springs laboratory is located at AZRI and services the Southern Region of the NT.
Alice Springs lab 2004-05 Difference from 2003-04 Total samples 2285 7.2% decrease PWC samples (all) 2072 6.8% decrease NT Government 42 64.4% decrease* Sewage (all) 190 48.8% decrease** Submissions 171 43.7% increase*** Total tests (determinations) 7199 10.3% decrease • Submissions increased 43.7% from 2003-04 numbers • Samples decreased 7.2% from 2003-04 numbers • There are no major new clients * Government samples show a significant decrease because roadside rest areas are no longer routinely monitored ** Sewage samples show a significant decrease due to many of the sewage ponds not containing water *** Submissions show a significant increase due to new legislation which requires private enterprises which provide a food service to test their water annually
Current Alice Springs staff consists of:
Belinda Sanderson Tracey May
149 Resource Protection
RESOURCE PROTECTION SERVICE: PLANT HEALTH (PRODUCTION)
Program: Plant Health (Production)
PROJECT: Arthropod Identification and Control Service
Project Officers: D. Chin, H. Brown, B. M. Thistleton, M. Neal, M. Hoskins, H. Wallace, G.R. Brown and L. Zhang
Location: NT-Wide
Objective:
To provide accurate advice on the identification and control of agricultural, horticultural and domestic arthropods to primary producers, government personnel, pest control operators and the general public.
Background:
The Section provides an advisory service on entomological matters pertaining to agricultural, horticultural or domestic situations. Extension enquiries include phone calls for identification and advice on control of insects, grower visits, examination of specimens delivered to DPIFM offices; talks provided to industry organisations, schools and the university; and presentations at departmental field days, rural, horticultural and agricultural shows. The nature of enquiries and the recommendations provided are recorded on a database. The information recorded may be used for future planning of research and allocation of resources.
Results:
During the year, the Section received 1051 enquiries. The proportions of enquiries received from each client category in 2004-05 compared with 2003-04 are shown in Table 1.
Table1. Enquiries received from each client category
2004-05 2004-05 2003-04 Enquiry type Number % % Government 235 22 21 Household 255 24 26 Growers 430 41 35 Other 103 10 15 PCO 28 3 3 Total 1051 100 100
The proportion of each category remained at the same ranking when compared with 2003-2004. However, in 2004-05 there was an increase of 288 in total enquiries.
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Extension trends and enquiries of interest
Grower enquiries
• Control of Scirtothrips dorsalis Hood sp. (Thysanoptera: Thripidae) in grapes was discussed with a Katherine grower (July 2004).
• Graptostethus (Hemiptera: Lygaeidae) swarms were observed in mango orchards, causing scratching damage to mango flowers (July 2004).
• Swarms of Leptocorisa acuta Thunberg (Hemiptera: Alydidae) and Gralliclava horrens Dohrn (Hemiptera: Coreidae) were recorded on palms at a nursery in Howard Springs (July 2004).
• A nursery grower in Howard Springs effectively controlled two spotted mites, Tetranychus urticae Koch (Acarina: Tetranychidae) with the recommendation of Neemtech potassium soap and canola oil on cordyline. The same treatment was applied last year to other nursery plants with similar results (August 2004).
• Growers have reported that trichlorfon is not effective in controlling mango leafhopper Idioscopus nitidulus (Walker) (Hemiptera: Cicadellidae) (September 2004).
• Graptostethus (Hemiptera: Lygaeidae) swarms were reported in commercial crops of mangoes (September 2004; April 2005), okra (February 2005) and watermelons (April 2005).
• Striped mealybug, Ferrisia virgata (Cockerell), (Hemiptera: Pseudococcidae) was identified on mango fruit in Katherine orchards (September 2004).
• Significant pests in mango orchards were observed (October 2004).
• Mango planthopper, Colgaroides acuminata (Walker) (Hemiptera: Flatidae) – 90-100% of fruit damaged on most trees in an orchard of 761 trees.
• Mango scale, Pseudalacaspis cockerelli (Cooley) (Hemiptera: Diaspididae) – high infestation on fruit in a neglected orchard where the entire crop was not marketable.
• A fig grower who previously had problems with dried fruit beetles (Coleoptera: Nitidulidae) attacking ripe fruit, reported that the fermented apple juice traps developed and recommended by the Section in 2002 worked very well and that he had no further problems with this pest. The orchard now has fermented apple juice traps around the perimeter of the netted orchard (October 2004).
• A date farm near Alice Springs was visited to investigate damage to fruit by Coccotrypes sp. (Coleoptera: Curculionidae). It was found that the beetles were breeding in the previous season’s fallen fruit under the palms. A spray was recommended which reduced the population and the damage to the current season’s fruit. The grower was advised years to remove the fallen fruit after harvest in future (November 2004).
• Advice was provided to a grower on the treatment of large consignments of mango seedlings for export to Queensland (July 2005). Treatment advice was provided for mango seed weevil, mango leafhopper and ginger ants. (December 2004-January 2005)
• Myllocerus sp. (Coleoptera: Curculionidae) was recorded on two properties in Darwin and Katherine defoliating young mango trees (December 2004-January 2005).
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• Advice was provided to a lettuce grower in Alice Springs on the control of Frankliniella schultzei Trybom (Thysanoptera: Thripidae) which transmits the tomato spotted wilt virus and which was recently detected in the crop (December 2004/January 2005).
• Damage was reported to rockmelon seedlings in Katherine and a sample of adult false wireworm beetles, Caedius sphaeroides Hope, (Coleoptera: Tenebrionidae) was submitted. The grower’s block has a history of seedling damage caused by this pest. (March 2005)
• Small pointed snails, Cochlicella barbara (Linnaeus) (Eupulmonata: Helicidae) were collected from a market garden in Alice Springs (May 2005). The species had first been noted there in June 2004.
• Flea beetles, Aphthona sp. (Coleoptera: Chrysomelidae) on flower panicles in a mango orchard were submitted for identification. The beetles were not causing any damage to the flowers or to the developing fruit (May 2005).
• Flower caterpillars and Graptostethus sp. (Hemiptera: Lygaeidae) were noticed causing damage to mango flower panicles on a large commercial mango orchard (May 2005).
• A specimen of the big-eyed bug Geocoris lubrus Kirkaldy (Hemiptera: Lygaeidae) was collected from carambola fruit in an orchard at Acacia. The bug is a predator of mites, thrips, aphids, small caterpillars and insect eggs (May 2005).
• Mango leafhopper infestations were detected in Pine Creek and Katherine (June 2005).
• Advice on control was provided to a grower for longicorn larvae in the trunks of pawpaw plants. The infestation was secondary damage as the beetles attacked pawpaw trunks that had been already weakened by oriental scale (June 2005).
Government enquiries
• The detection of a northern mouse spider, Missulena pruinosa Levitt-Gregg (male) (Araneida: Actinopodidae) in a correctional services office at Berrimah was one of the first sightings of this spider for the season (August 2004).
• A larva and adult of Dermestes maculatus (De Geer) (Coleoptera: Dermestidae) were identified from a sample submitted by Medical Entomology. The specimen was collected from a mummified body in Katherine (October 2004).
• About a 150-year old banyan tree was inspected for the Darwin City Council. Longicorn beetles had been attacking large sections of the branches and aerial roots. The tree was situated in the centre of a park, overhanging playground equipment. There was a safety concern for children playing under it. Samples were collected and Acalolepta mixtus (Hope) (Coleoptera: Cerambycidae) was reared from an infested branch. This is the same species as the longicorn pest of mangoes. Other banyan trees in the city generally associated with stress factors have also been attacked by this beetle (October 2004).
• Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) was collected from Mimosa pigra in the Weeds Bio- Control shade house (November 2004).
• Longan fruit infested with caterpillars and secondary pests such as elaterids and nitidulids were collected from the Coastal Plains Horticultural Research Station. The caterpillars were reared and identified as Conogethes punctiferalis complex (Lepidoptera: Pyralidae) (December 2004-January 2005).
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• NT Quarantine submitted three fruit fly larvae collected from an infested mango from Qld sold at a supermarket in Alice Springs. The larvae were sent interstate for DNA analysis and were identified as Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) (February 2005).
• A banyan tree with cerabycid damage in a park at the Narrows was inspected. Samples of the aerial roots containing cerambycid larvae were collected (February 2005).
• An environmental health officer submitted a caterpillar which was found in a brand of tinned curry imported from Thailand. It was the eggfruit caterpillar Sceliodes cordalis (Doubleday) (Lepidoptera: Pyralidae) (March 2005).
• Samples of Crioceris nigripes Fabricius (Coleoptera: Chysomelidae) were collected from cycads at a public swimming pool. Low toxic sprays were suggested for control (April 2005).
• A rural police station reported an infestation of spiders in its communications room. They were identified as brown widow spiders, Latrodectus geometricus C.L. Koch (Araneidae: Theridiidae) (April 2005).
• Insects collected on sticky board traps from the National Archives building in Millner were identified. None were potential pests for the archive collection (May 2005).
Household and home garden enquiries
• Longicorn damage was diagnosed on an old dying banyan tree in Parap (July 2004).
• Brithys crini (Fabricius) (Lepidoptera: Noctuidae) was recorded from Crinium lily and Hypeastrum lily (July 2004).
• A sample of rat tail larvae (Diptera: Syrphidae) was collected from liquid manure (September 2004).
• Several mango leafhopper enquiries for information on control were received from home gardeners and from a Buddhist Centre (November 2004).
• A householder in Brinkin requested advice on the control of extensive nests of Trigona sp. (Hymenoptera: Apidae) in the walls of the house. The nests had been in the house for several years (December 2004/January 2005).
• Two nests of Vespula germanica (Fabricius) (Hymenoptera: Vespidae) from two houses were detected and destroyed in Alice Springs (December 2004/January 2005).
• Identification and advice was provided for soldier fly larvae on a lawn (Diptera: Stratiomyidae) (February 2005).
• Advice was provided to treat a heavy infestation of Lasioderma serricorne (Fabricius) (Coleoptera: Anobiidae) in aboriginal beads (Eucalyptus seed capsules) (March 2005).
• Two barking spiders, Selenocosmia spp. (Araneae: Theraphosidae) from the Katherine area were submitted for identification (March 2005).
• Large numbers of brown widow spiders, Latrodectus geometricus C.L. Koch (Araneida: Theridiidae) were recorded from under chairs outside a home (April 2005).
• A gordian worm (Phylum Nematomorpha) which emerged from the abdomen of a praying mantid was submitted for identification (April 2005).
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• Two homes in Batchelor reported invasions of small black beetles. They were identified as Limnichus sp. (Coleoptera: Limnichidae). The beetles are attracted to lights and were probably breeding in nearby damp leaf litter (May 2005).
• A native cockroach, Megazosteria patula (Walker) (Blattodea: Blattidae) was submitted for identification after it had caused a severe allergic reaction by squirting defensive secretions onto the face of a cat (June 2005).
Other public enquiries
• An enquiry was received from Roadkill Café on how to culture and slaughter green tree frogs. There is a demand for frog meat since the ban on the import of frog meat. It was referred to Parks and Wildlife for permits (August 2004).
• A childcare centre reported wasps were nesting in a sandpit. The wasps were identified as Tachysphex sp. (Hymenoptera: Sphecidae) which are unlikely to attack people unless handled or picked up when injured. Wasps in this group nest in the ground and prey on insects such as grasshoppers, praying mantises and cockroaches. Another sighting of these wasps was at the Berrimah Police Station (September 2004).
• Suspect exotic snails were collected from a pet shop in Katherine. The snails were identified as Pseudosuccinea columella Say (Hemiptera: Lymnaeidae (naturalised in southern Australia but not the NT) and Gyraulus gilberterti Dunker (Hemiptera: Planorbidae), which has been recorded in Australia (September 2004).
• A dead Eucalyptus tetradonta in Katherine was heavily infested with cerambycid larvae, a few larvae of Elateridae, and large numbers of Mastotermes darwiniensis (Froggatt) (Isoptera: Mastotermitidae) (February 2005).
• Bostrychopsis jesuita (Fabricius) (Coleoptera: Bostrichidae) adults were caught chewing holes into cotton canvas tents in Alice Springs (October 2004).
• A retailer in Nhulunbuy submitted 12 trays of cigars which were heavily infested with Lasioderma serricorne (Fabricius) (Coleoptera: Anobiidae) (April 2005).
Ant enquiries (identification or control)
• Advice was provided for the control of Odontomachus turneri Forel (Hymenoptera: Formicidae) in the 1.4 ha garden of Government House (December 2004-January 2005).
• Ants that were reported to have stung people in Alice Springs were identified as Rhytidoponera sp. (Hymenoptera: Formicidae) (March 2005).
• Oecophylla smaragdina (Fabricius) (Hymenoptera: Formicidae) was reported in several cases to attack injured wildlife in a sanctuary (May 2005).
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PROJECT: Development of IPM in Citrus – Biological Control of the Citrus Leaf Miner
Project Officers: M. Hoskins, H. Wallace and B. M. Thistleton
Location: Top End properties
Objective:
To introduce and monitor Ageniaspis citricola (Hymenoptera: Encyrtidae), a parasite of the citrus leaf miner.
Background:
Larvae of the citrus leaf miner, Phyllocnistis citrella Stainton, (Lepidoptera: Gracillariidae) feed beneath the epidermal layer of young leaves of various species and varieties of citrus. When young plants are continuously attacked, their growth can be retarded.
As they feed, larvae leave behind twisting silvery trails of faecal matter. Light feeding (less than two mines per leaf) results in leaves becoming slightly distorted or curled but they are normally retained on the tree. Old larval mines will persist as scarring on the leaf surface. Heavy infestations (more than six mines per leaf) often results in localised necrosis of leaf tissue, severely reducing the plant’s photosynthetic capacity.
The citrus industry identified the need for biological control of the citrus leaf miner to reduce its impact on citrus plantings.
Biological control
In southern States the most effective wasp parasites of the citrus leaf miner are Ageniaspis citricola Logvinovskaya (Hymenoptera: Encyrtidae) and Cirrospilus quadristriatus Subba Roa and Ramamani (Hymenoptera: Eulophidae), both of which were introduced into Australia from South-East Asia in 1990-92. In Queensland, levels of parasitism of larvae by A. citricola reach 90% by February-March. Overseas, A. citricola has established in most Mediterranean citrus growing areas such as Morocco, Israel and Turkey. In Florida it has become the dominant parasite with parasitism levels commonly reaching 100%.
During March and April of 1996-97 five small consignments of citrus leaf miner parasitoids were obtained from southern Queensland. Each batch contained approximately 50-80 wasps, comprised mainly of A. citricola, with some C. quadristriatus and Citrostichus phyllocnistoides (Narayanan) (Hymenoptera: Eulophidae). The wasps were released at the Katherine Research Station with one possible recovery of C. quadristriatus made several weeks after releases, but none of the species released was subsequently found to have established.
Method:
A consignment of parasite pupae from the Queensland Department of Primary Industries and Fisheries was received in Darwin on 20 April. Leaf material with emerging wasps was maintained in the Berrimah Farm Entomology insectary until the first batch of wasps was released on 22 April. Approximately 408 A. citricola were released in an orchard in Bees Creek growing mainly lime trees. The remaining leaf material was transported to Katherine where approximately 510 wasps were released amongst young lemon trees, over a three-day period (25 to 27 April). After release of the parasites, all leaf material and packing was destroyed.
Monitoring for establishment of the first generation of wasps was made at regular intervals starting two weeks after releases.
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Results:
At both release sites there was evidence that the parasites had completed at least one generation in the field. Monitoring is continuing.
If, over time, wasp populations become abundant, wasp pupae could be collected and redistributed to other orchards. This would be of great benefit. However, if wasps do not establish due to unforeseen circumstances, such as unfavourable weather, absence of leaf miner populations, or chemical drift, further consignments could be imported from Queensland next year.
PROJECT: The NT Insects Website
Project Officers: B. M. Thistleton, G. R. Brown, D. Chin, H. Brown, M. Hoskins, H. Wallace, L. Zhang and M. Neal
Location: Berrimah Farm and Katherine Research Station
Objective:
To provide insect fact sheets through a database system capable of holding large amounts of information on agricultural pests and their control, and dynamic web pages to access this information and make it readily available to clients.
Background:
The Department considers the Internet a key medium for information dissemination to its clients and staff. The Entomology Unit of the Plant Health Branch provides information to its large client base on a wide variety of insect and mite problems. Information on many of these problems has been published in Agnotes, crop books and posters. However, there are many problems on which there is no readily available information. The expansion of this data collection process is therefore necessarily an ongoing process. In line with the Department's policy, the section is actively seeking ways to effectively store and disseminate this information, and the use of the internet is seen as the preferred option.
A database-driven website was therefore developed which allows users to search for information by selecting lists of insects by common name, host, damage type, or taxonomic group, which leads them to data on groups of insects or individual species. This information is presented in datasheets showing details of biology, damage, monitoring and control, and to which are attached a number of pictures accessed through thumbnail images. Both the fact sheets and the associated images can be printed. More details can be found in the 2003-04 Technical Annual Report.
Results:
The website was launched at the Royal Darwin Show on 23 July 2004 and was promoted through the media and promotional handouts.
During the year 104 fact sheets were published on the website and a further 24 were published as photographs only.
There were 3597 visits to the website by 1856 separate visitors; there were 504 repeat visits. On average, there were 39 visits per day for the year, of which 22 were new and 17 were repeats.
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PROJECT: Control of Arthropods and Development of IPM in Tropical Fruit Crops
Project Officers: D. Chin, H. Brown, M. Hoskins and B. M. Thistleton
Location: Top End properties
Objective:
To identify potential arthropod problems in mango and other tropical tree crops and devise appropriate control measures.
Background:
Mangoes are the most important horticultural crop in the NT and receive a proportionate amount of resources from the Entomology Section. New problems appear each year for mango producers as this is a relatively new crop which continues to expand in area and value, and as new growers enter the production phase.
Horticultural officers, commercial growers and urban backyard producers frequently refer pest problems to the Section for advice or comment. Investigations help to detect new or potentially damaging insect problems. The Section is committed to provide advice and assistance to all growers, consistent with the aim of developing integrated pest management (IPM) systems for all tropical tree crops.
During 2004-05 the Section concentrated its research on mangoes, citrus (results in a separate report), rambutan, carambola, jackfruit and dragon fruit. However, identification and pest management advice was also provided for other tropical fruits.
Method and Results:
Mango flower thrips and their effect on fruit quality
Two properties growing Kensington Pride mangoes in Katherine were monitored for mango flower thrips between June 2004 and October 2004. Monitoring sessions were carried out three times which coincided with flowering, fruit-set and fruit maturity (prior to harvest). Orchard 1 was sprayed regularly for thrips (with limited control) and Orchard 2 was rarely treated with pesticides and incorporated biological farming practices. Flower panicles and small developing fruit were sampled for diversity and density of thrips. In previous years developing fruit from 3 to 30 mm in length were the most vulnerable to attack by thrips. The feeding damage first appears as rough white or pale patches which may expand as the fruit increases in size. Sometimes old damage from thrips can be confused with that caused by Campylomma austrina Malipatil (Hemiptera: Miridae). However, when fresh damage is examined the two types of damage are quite distinct. C. austrina damage is usually associated with “pits” or “dimples”.
Most of the thrips species sampled are pollinators or predators. However, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) feeds on new flush and is also found in flowers and on developing fruit-lets. S. dorsalis has been suspected of feeding on the developing fruit that is up to 30 mm in length. Samples of developing fruit were tagged and monitored throughout the season but the results did not confirm which species were involved in damaging the fruit. Although damage was observed on the fruit and various samples of thrips were collected from damaged fruit, the thrips were nymphs and could not be confirmed to species level.
The species range and mean number of thrips per panicle is shown in Table 1 for the first two sample periods. In the flower panicle samples from Orchard 1 there were thrips from all six categories (Thrips spp.
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(Thysanoptera: Thripidae), Frankliniella schultzei Trybom (Thysanoptera: Thripidae), Scirtothrips dorsalis Hood (Thysanoptera: Thripidae), Haplothrips spp. (Thysanoptera: Phlaeothripidae), Phlaeothripidae nymphs (Thysanoptera: Phlaeothripidae) and Thripidae nymphs (Thysanoptera: Thripidae)). The samples from this orchard also contained higher numbers of all species when compared with Orchard 2 which had lower numbers of thrips. Scirtothrips dorsalis was present in low numbers in orchard 1 but was absent in flower and fruit panicle samples collected from Orchard 2.
Observations on damage to the skin of developing fruit are shown in Table 2. The damage was estimated in percentages of the surface area of damage in square millimetres. Measurements are listed in Table 2 as percentage of surface area of the skin damaged. The mean size of 50 sampled and tagged fruit is shown in the Table with the mean surface area or proportion of damaged skin caused by thrips. The fruit-lets in orchard 1 had a substantially higher surface area of blemished skin (20.88 - 24.72%) compared with orchard 2 (4.28 - 5.88%).
Table1. The diversity and density of thrips in flower and fruit-let panicles
Species Mean number of thrips per Mean number of thrips per fruit- flower panicle let panicle (fruit-let size 3-30 mm) Orchard 1 Orchard 2 Orchard 1 Orchard 2 29/06/04 30/06/04 02/09/04 03/09/04 (No. of panicles (No. of panicles (No. of panicles (No. of panicles sampled = 9) sampled =10) sampled =19) sampled =10) Thrips spp. 17.33 2.40 0.89 1.20 Frankliniella spp. 9.67 1.90 0.04 0 Scirtothrips spp. 0.67 0 0.48 0 Haplothrips spp. 3.67 0.40 0 0 Phlaeothripidae nymphs 2.22 1.40 0.11 0.10 Thripidae nymphs 122.67 25.60 3.18 3.0
Table 2. Observations on thrips damage to the skin of developing fruit
Property Date Mean fruit Surface area of the size (mm) skin blemished (%) Orchard 1 22/09/04 40.46 24.72 Orchard 1 19/10/04 85.32 20.88 Orchard 2 23/09/04 46.18 4.28 Orchard 2 20/10/04 93.82 5.88
Mango IPM
Three orchards in the Katherine region were monitored fortnightly during each season for the last three years. The work carried out in 2004-05 completes the monitoring sessions required for the project which will be reported in a separate publication to include the results from previous years.
During 2004-05 results from monitoring sessions indicated that the main pests found in orchards were mango scale, Pseudaulacaspis cockerelli (Cooley) (Hemiptera: Diaspididae), tea mosquito bug, Helopeltis pernicialis, Stonedahl, Malipatil and Houston (Hemiptera: Miridae) and planthoppers; Colgaroides acuminata (Walker) (Hemiptera: Flatidae) and Siphanta spp. (Hemiptera: Flatidae).
Detection of mango leafhoppers in Pine Creek and Katherine
In June 2005, mango leafhoppers, Idioscopus nitidulus (Walker) (Hemiptera: Ciccadellidae) were detected at a small number of properties in Pine Creek and Katherine. Growers in these areas were informed of the pest and control treatments carried out on known infested properties.
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Rambutan IPM
A workshop was conducted for rambutan growers to present a new insect monitoring manual, orchard monitoring software and a poster on pests and natural enemies developed by QDPI&F and DPIFM. Training on the use of the orchard monitoring software was also provided.
Several properties were monitored during the flowering and fruiting period to provide assistance to growers on how to monitor and to demonstrate the use of orchard monitoring software. The main pests seen during monitoring sessions were Icerya seychellarum (Westwood) (Hemiptera: Margarodidae), Icerya aegyptiaca (Douglas) (Hemiptera: Margarodidae), Pulvinaria psidii Maskell (Hemiptera: Coccidae) and Ferrisia virgata (Cockerell) (Hemiptera: Pseudococcidae). Each of two properties that rely on biological control of scales, mealybugs and fluted scales with Cryptolaemus montrouzeri Mulsant (Coleoptera: Coccinellidae), we found five C. montrouzeri per 20 trees.
Control of the two-spotted mite with predatory mites in a netted carambola orchard
A netted carambola orchard containing 1000 trees at Acacia Hills has been experiencing difficulty in controlling the two-spotted mite, Tetranychus urticae Koch (Acarina: Tetranychidae). In previous years the infestation of T.urticae has been very high in this orchard, to the extent that many trees were stressed and had yellowing leaves. A number of different pesticides such as dimethoate, carbaryl and miticides, had been used on a regular basis with limited success. During the 2003-04, season a small trial was carried out to test two species of commercially available predatory mites, Typhlodromus occidentalis Nesbitt (Acarina: Phytoseiidae) and the Chilean predatory mite, Phytoseiulus persimilis Athias-Henriot (Acarina: Phytoseiidae). Both species were effective in controlling T. urticae but P. persimilis was more suited to the high humidity in the netted orchard.
A new trial on the control of the two-spotted mite T. urticae on carambolas was commenced in June 2004. A baseline count was determined for the level of T. urticae on carambola leaves (on 24 June 2004) and then 20 000 P. persimilis were released on 8 July 2004. A further 10 000 P. persimilis were released each on 22 and 29 July 2004. The results of the population density of T. urticae and P. persimilis are shown in Figure 1.
Leaf samples were collected randomly from the orchard to assess mite populations. During the period from 24 June 2004 to 29 July 2004, the sample size was 50 leaves and for the remainder of the sample dates, 250 leaves were sampled. Sampling was carried out at two to three-week intervals from June 2004 to September 2004 and then less regularly from September 2004 to June 2005.
In 2004 the time required for P. persimilis to establish enough to control T. urticae was almost seven weeks. These results are typical of the establishment period for P. persimilis according to the supplier. The level of T. urticae fluctuated from less than one to three per leaf. The population of P. persimilis peaked at 13 (seven weeks after release) and then maintained populations between seven and one (the number of P. persimilis is measured as the total number detected per 250 leaves).
The population of mites in the orchard over the wet season from December to February is generally very low to nil due to heavy rainfall. Sampling re-commenced in February 2005. Between February 2005 and June 2005 no mites were detected in the orchard. However, in June 2005 just prior to release of 40 000 P. persimilis, there were five T. urticae eggs per 250 leaves sampled.
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14 12 10 T. urticae 8 P. persimilis 6 4 2 0 Number of mites per leaf sample 24/06/2004 24/07/2004 24/08/2004 24/09/2004 24/10/2004 24/11/2004 24/12/2004 24/01/2005 24/02/2005 24/03/2005 24/04/2005 24/05/2005 24/06/2005 Date
Note: The leaf sample size was 50 leaves for 24 June 2004 to 29 July 2004 and 250 leaves for the remainder of the sample dates
Figure 1. The number of Tetranychus urticae and Phytoseiulus persimilis collected in leaf samples from the carambola orchard
Treatment of various ant species in orchards and home gardens with an insect growth regulator bait
Trials were conducted to test an insect growth regulator in a bait formulation for a chemical company. The bait was tested against several species of pest ants in commercial orchards as well as home gardens in Darwin and Katherine.
The trials in Darwin included tests in commercial orchards against the ant species listed:
• Jackfruit – Pheidole megacephala (Fabricius) (Hymenoptera: Formicidae)
• Dragon fruit –Iridomyrmex sp. A (gracilis gp), Iridomyrmex ANA sp. 4 and Iridomyrmex ANA sp. 3 (mattiroloi gp) (Hymenoptera: Formicidae)
• Rambutan – Oecophylla smaragdina (Fabricius) (Hymenoptera: Formicidae)
Trials were also conducted for P. megacephala in five home gardens in both Darwin and Katherine.
The treatments were successful in reducing the population of P. megacephala in home garden blocks and in the commercial jackfruit orchard by 95 -100%. However, the treatments applied to the dragon fruit and rambutan blocks had a limited effect on O. smaragdina and Iridomyrmex spp. and there was no significant reduction in the size of the colonies.
Further details of the trials were documented in two separate reports submitted to the chemical company.
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PROJECT: The Northern Territory Economic Insect Reference Collection
Project Officers: H. Brown, M. Hoskins, H. Wallace, B. M. Thistleton, G. R. Brown and L. Zhang
Location: Berrimah Farm and the Katherine Research Station
Objective:
To develop, curate and maintain a reference collection of economically important arthropods relevant to various NT agricultural and horticultural industries and to develop and maintain a suitable, retrievable database of all specimens held in the collection.
Background:
The insect reference collection was initiated in 1970 to become the main insect reference collection in the NT. Over the years, the collection expanded to include economically important arthropods from agricultural, horticultural and domestic sources as well as from general collection. In 1992, the majority of the non- economic specimens were donated and transferred to the NT Museum.
Results:
During the year a total of 912 specimens were added to the database which brings the total to 40 415.
During 2004-05 the Section forwarded 68 specimens to specialist taxonomists for species identification or confirmation. Most specimens were of economic significance. A further 25 specimens were lent to specialists for study.
The following were newly recorded in 2004-05. They are indicated as a new regional or country locality (New NT, New Aust.) or new host records for the NT (New host).
ACARINA
Tetranychidae • Brevipalpus phoenicis (Geijskes) - ex. leaf of Averrhoa carambola (New host) • Eutetranychus orientalis (Klein) - (M218, M219) on Cassava (New host) • Polyphagotarsonemus latus (Banks) - ex. leaves of silver beet (New host) • Tetranychus sp. - (M220) on grape leaves (New host)
COLEOPTERA
Cerambycidae • Acalolepta mixtus (Hope) - ex. Ficus virens branches and aerial roots (New host)
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Nitidulidae • Carpophilus mutilatus Erichson - ex. fermented apple juice traps (New NT) • Epuraea subluteola Kirejtshuk - ex. fermented apple juice traps (New NT) • Urophorus humeralis (Fabricius) - ex. fermented apple juice traps (New NT)
DIPTERA
Tephritidae • Bactrocera aquilonis (May) - ex. Polyalthia longifolia fruit (New host) • Bactrocera melanothoracica - ex. ME trap (New NT)
HEMIPTERA
Diaspididae • Pinnaspis strachani (Cooley) - ex. leaves of Citrus sp (New host) Margarodidae • Icerya seychellarum (Westwood) - ex. stems of Acalypha wilkensiana (New host) Pseudococcidae • Ferrisia virgata (Cockerell) - (T518) on Cotton plants (New host) - ex. Psidium guajava (New host)
HYMENOPTERA
Pergidae • Dalia graminis Schmidt and Brown - ex. Pennisetum typhoidew (New Aust.) Vespidae • Vespula germanica (Fabricius) - ex. nests from two houses in Alice Springs. These nests have been eradicated (New NT)
LEPIDOPTERA
Pyralidae • Conogethes punctiferalis complex (Guenee) - reared from fruit of Euphoria longan (New host)
THYSANOPTERA
Thripidae • Scirtothrips dorsalis Hood ex. Mimosa pigra (New host)
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PROJECT: Pest Management in Ornamentals – Alpinia Borer
Project Officers: H. Wallace, M. Neal and B. M. Thistleton
Location: Darwin Region
Objective:
To advise on management of pests of ornamentals and to carry out research on key pests.
Background:
A stem boring moth, Conogethes pluto Butler (Lepidoptera: Pyralidae), which causes damage to Alpinia plants, has developed into a significant pest over the last few years. A research program is being conducted to find methods to control this insect. The species C. pluto is closely related to the yellow peach moth, Conogethes punctiferalis.
Method:
Monitoring of damage caused by C. pluto was started on three properties in January 2004. Since it is not easy to find the eggs, and since the larvae are hidden inside the stem, the monitoring was based on the presence of holes in the stem and whether these had new or old frass. Data was collected from small, medium and large stems.
A spray regime with permethrin was also initiated by project staff on one of these properties in January 2004 and the owner of a second property also sprayed. Spray decisions were based on the monitoring results. No spraying was carried out on the third property.
Field-collected larvae were bred in the laboratory to obtain information on development times. Adults which emerged in the laboratory were released into cages with Alpinia plants for observations on egg laying.
Two synthetic pheromones which attract Conogethes punctiferalis were supplied by Dr Andy Gibb, HortResearch, Canterbury, New Zealand. These were tested in two experiments at four different sites to compare both pheromones at the same concentration and in a third experiment at one site to test one pheromone at different concentrations.
Specimens were sent to Dr Karen Armstrong, Lincoln University, Canterbury, New Zealand for DNA analysis. This will confirm if C. pluto and C. puntiferalis are indeed distinct species.
Trichogramma pretisoum has been recorded as a parasite of the eggs of the closely related Conogethes punctiferalis. Releases of this parasite commenced on one property in June.
Results:
Seasonal fluctuations in populations for two properties for the period January 2004 to February 2005 are shown in Figure 1. This is based on the presence of holes with new frass which indicates that a larva is present in the stem. Figure 1 shows that populations are present throughout the year and that the permethrin spray regime gave good control.
Details of the caterpillar and pupal stages of the moth are now available, although no egg-laying has yet been recorded in the cages.
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Neither of the two pheromones attracted the moths, which gives further evidence that C. pluto and C. puntiferalis are distinct species. Dr Gibb is interested in working on C. pluto, to see if he can extract and later synthesise a pheromone specific to this species.
Parasite releases are ongoing and results will be reported next year.
The data was presented to the cut-flower group of the NTHA at a meeting held in June.
20 1st spray property 2 Last spray property 2 15 Property 1 - unsprayed
10 Property 2 - sprayed 5
% of stems with new frass new with of stems frass % 0
4 4 04 04 05 n 04 b 04 r n 04 v 04 n 05 e Jul 04 ct 0 o Ja F Mar Ap May 04 Ju Aug 04 Sep 04 O N Dec 0 Ja Feb
Figure1. Incidence of Congethes pluto on two properties
PROJECT: Management and Control of Termite Pests of Horticultural Crops in the Northern Territory
Project Officers: B. M. Thistleton and M. Neal
Location: NT
Objective:
To develop effective environmentally sustainable control methods against Mastotermes darwiniensis and other termites in horticultural crops in the Northern Territory.
Background:
Mastotermes darwiniensis Froggatt (Isoptera: Mastotermitidae) is the most destructive species of termite in tropical Australia. In the Northern Territory this species accounts for substantial annual production losses in horticultural tree crops and is also responsible for losses in vegetable and agricultural crops. M. darwiniensis can cause major damage to buildings, wooden structures, electrical cables and a variety of other materials. The main product registered for use in horticulture against this pest is Mirant containing the organochlorine mirex. With organochlorines being phased out it is necessary that alternative pesticides be tested against M. darwiniensis. Microcerotermes distinctus Sylvestri and M. implacidus Hill (Isoptera: Termitidae) are also a problem in young citrus and young and bearing grapevines, respectively.
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Method and Results:
During the year a number of trials were carried out to continue to test the effect of Termidor Residual Termiticide® (Termidor) containing 100 g/L fipronil applied by soil injection, through the irrigation line or directly into the trunks of trees, on M. darwiniensis and Microcerotermes spp. Details of the methods can be found in the 2002-03 Technical Annual Report
Long term management of Mastotermes in mango trees
A soil injection trial on mature mango trees was conducted in Humpty Doo commencing in June 2001 (see previous Technical Annual Reports for details). The original aim of this trial was to assess the control given by the insecticide and to provide samples of fruit for measurement of residues. The trial was extended to investigate if reinvasion of the trees could be prevented by monitoring and controlling termite activity on the edge of the block. A line of wooden billets had been dug into the soil along one edge of the block. The billets and the trees, which had been drilled at the beginning of the trial, were assessed for termite activity at regular intervals since 2001. On several occasions activity was found in one of the billets and each time an aggregation drum was set up at the site. Once active, the site was treated with Termidor as a soil injection. Several trees outside the original experimental area were infested and an aggregation drum on a billet site was treated in June 2004. An assessment in July 2004 showed that activity had ceased in all these trees. The trees in the original trial area had therefore been kept free of M. darwiniensis for three years.
Soil injection for Mastotermes on mature mango trees
A trial was conducted in May 2003 by injecting every second mango tree in a block at Coastal Plains Horticulture Research Farm (see the 2002-03 Technical Annual Report). In this trial pest activity ceased in all trees but monitoring was continued to establish the time before re-invasion occurred and if this period was different for treated and untreated trees. This would indicate if there was any long term residual effect of the chemical. To date only four trees have become reinfested and monitoring is continuing.
Trunk injection trials for Mastotermes in mango trees
A previous trial, which was reported in the 2004 Technical Annual Report, showed that Termidor applied through holes drilled into termite galleries in the trunks of amenity trees gave very effective control of M. darwiniensis. A trial was therefore set up at Berry Springs in June 2004 to test if this application method would also be effective in mango trees and to test fruit for residue. Three rows of 33-35 mango trees were drilled and assessed for activity. Four trees were treated with Termidor in late June and assessments were carried out throughout July, by which time activity had ceased in the treated trees and all the other trees in the experimental area. Samples of fruit were taken from the treated trees in October for residue tests. No residues of fipronil were detected.
Mastotermes in cashew trees
Trials were commenced at Wildman River where extensive new plantings of cashews have been established. Investigations by drilling into the trunks of trees in uncleared areas showed that while many were hollow, the invading termites were mainly Coptotermes acinaciformis, rather than M. darwiniensis. This is the typical situation in areas of natural bush where M. darwiniensis is often only present in small colonies.
In planted areas however, M. darwiniensis, often build up into huge colonies covering considerable areas. This is the case in parts of the old blocks of cashews at Wildman River. Control of the termites in these areas would therefore reduce the risk of migration into the new plantings. A trial was therefore commenced to test Termidor in this situation using the techniques developed for mangoes and citrus. In this preliminary trial the termite infestation in part of a block of cashews was mapped by drilling the trunks and assessing for subsequent blocking of the holes with mud by the termites. A heavily infested dead tree was treated with Termidor and its effect on termite activity in this tree and in other trees at varying distances was assessed.
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Further trials will treat a grid of trees to investigate if colonies can be eliminated from infested areas and residue tests of fruit will be carried out.
The newly planted blocks are being monitored by the plantation staff for damage by M. darwiniensis but none have been detected yet. Since termite populations in the young trees will be low, a more efficient dissemination of the chemical would be achieved by aggregating populations into drums before treatment. This has been recommended to the plantation management and the use of drums has been demonstrated.
Microcerotermes in citrus trees
Assistance was given to a plantation in Katherine in managing M. darwiniensis in non-bearing citrus trees. All the trees on the plantation had previously been treated by soil injection, but there were still pockets of activity by termites. Where trees had been killed aggregation drums were set up. The number of termites aggregated into the drums was relatively low and in some cases they were covered in mites. This suggested that only small and unhealthy populations remained and the drums were treated to control them.
Microcerotermes on grapevines
A final assessment was carried out in September on two trials on newly-planted grapevines at Ti Tree. These trials were set up in September 2003 and consisted of four treatments of Termidor (two different rates and two different timings) applied through the irrigation line, with a treatment of the standard chlorpyrifos butt spray and an untreated control. In one property M. implacidus infestation increased soon after treatment and excellent control was obtained with the chemigation treatments. In the other property the infestation rate was too low for effects of the treatment to be evident.
A new trial to test Termidor on mature grapevines was set up in September. The trial consisted of two rates applied through the irrigation line, plus an untreated control. The treatments were replicated four times in a randomised complete blocks design. Control was not very good as in young vines, as much of the termite activity was in the trunk and upper branches of the mature vines. However over time the populations decreased and by April there had been a 60% reduction in numbers of infested vines treated with the higher rate. A second application of Termidor at the same rates will be made in this trial in September 2005 to investigate if a further reduction can be obtained. A second trial using higher rates will also be conducted.
Minor use permits for Termidor
Assistance was provided to The NT Table Grape Producers Association with an application for a minor use permit for the use of Termidor on grapes, based on the results of the trials conducted at Ti Tree. The permit was issued by the Australian Pesticides and Veterinary Medicines Authority (APVMA) in September and the growers are now using this product.
An application was made to APVMA in March for a permit to use Termidor under aggregation drums and in sacrificial trees. Since this is the only method approved for Mirant®, this permit will allow for that product to be phased out.
Extension
Advice on control of termites using the methods developed was given to growers in Darwin and Katherine areas by phone, mail or, more usually, by visits.
Collaborative research
Assistance was given to visiting termite researchers from CSIRO on studies of Mastotermes and other termites in the NT. In particular, assistance was given in a trial to test a new product on Coptotermes acinaciformis under a sub-contract with CSIRO.
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Visitors to the Section included Dr Susan Jones, Department of Entomology, Ohio State University USA, Dr Tracie Jenkins, Department of Entomology, University of Georgia USA, and Scott Kleinsmidt, BASF. They took termites for research purposes. More samples of several species were subsequently sent to Dr Jenkins for DNA analysis.
PROJECT: Disease Diagnostic Service
Project Officers: R. Pitkethley, B. Condé, A. Daly, S. Bhuiyan, L. Ulyatt and I. Arao-Arao
Location: Darwin and Katherine
Objective:
To provide a plant disease diagnostic service to primary producers and the public.
Background:
Disease diagnosis continues to be a core function of the Plant Pathology Section. Together, the Darwin and Katherine plant disease diagnostic facilities form a node of the Northern Australian Diagnostic Network (NADN) established by the Cooperative Research Centre for Tropical Plant Protection of which DPIFM is a partner.
The appointment of a plant pathologist at the Katherine laboratory in May 2004 opened the way for improved service to industry in Katherine and Douglas Daly.
The Darwin Plant Pathology laboratory continued its involvement in the national grapevine leaf rust eradication program. In addition to research on the rust, the laboratory carries out a diagnostic function. Plant pathologists screen all grape leaf samples collected in the course of surveys to determine if rust is present.
Results:
In 2004-05, 1720 cases were processed in the Plant Pathology laboratory at Berrimah. The figure includes a significant number of grapevine leaf samples that were tested for rust in support of the national grapevine leaf rust eradication program. The Katherine laboratory processed 97 routine diagnoses. A further 1097 mango fruit samples were processed in the course of the sea-freight trial.
Progress was made in upgrading the Katherine laboratory with additional equipment. This allows the laboratory to act more independently and has enhanced its diagnostic capacity, enabling it to provide a more timely service to the area it serves.
Some cases of special interest
Cercospora guatamalensis, leaf spot of Ocimum basilicum (sweet basil) Fusarium oxysporum f.sp. basilici, wilt of Ocimum basilicum (sweet basil) Aecidium marsdeniae, rust of Marsdenia sp. Periconiella musae, Periconiella speckle of banana Veronaea musae, tropical speckle of Musa sp. (banana) Microsphaeropsis olivacea, associated with dieback of Parkinsonia aculeata Ganoderma sp., associated with dieback of Dypsis lutescens (golden cane palm) Ganoderma sp., associated with trunk rot of Carpentaria acuminata (Carpentaria palm) Phytophthora sp., leaf, stalk rot of Anthurium sp.
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Asperisporium caricae, black spot of Carica papaya (papaya) (intercepted on fruit in market) Dothiorella ‘long’, fruit rot of Mangifera indica (mango) Alternaria alternata, fruit rot of Mangifera indica (mango) Colletotrichum gloeosporioides, fruit rot of Mangifera indica (mango) Dothiorella dominicana, fruit rot of Mangifera indica (mango) Pestalotiopsis mangiferae, fruit rot of Mangifera indica (mango) Phomopsis mangiferae, fruit rot of Mangifera indica (mango) Cytosphaera mangiferae, fruit rot of Mangifera indica (mango) Colletotrichum acutatum, fruit rot of Mangifera indica (mango) Colletotrichum dematium, associated with leaf and petiole lesions on Arachis hypogaea (peanut)
Some detailed diagnoses
Jackfruit
Jackfruit tree and fruit problems were investigated in two areas, one with a fine soil type and the other with a gravelly soil. There appeared to be three main groupings of plant problems: rots due to pink disease, rots originating from branch and trunk injuries, and rots of the main root, associated with a basisiomycete. Some fruit developed fully, ready for market. However, a proportion of fruit at each locality failed to develop fully and trees were apparently thinned prematurely. Fruit stalks holding these fruit were brown in colour, often had a crack on one side and the internal stalk tissues were dry, without flowing latex associated with healthy jackfruit tissue. This appears to be a function of natural thinning related to the general vigour and health of trees. A small proportion of the under-developed jackfruit became infected with the fungus, Botryodiplodia theobromae (also recently called Diplodia theobromae).
Copper fungicides were recommended for the control of pink disease. The growers are applying agricultural lime to the base of jackfruit trees and at injuries in branches to reduce losses due to trunk rot, with apparent success. Growers were advised to apply lime at the drip zone for root absorption to raise the pH where soils were considered too acid. The jackfruit farmer on the better soil was also applying organic mulches. This was considered beneficial to root health and consequently to the overall health and vigour of the tree. The trees on the good soil were stronger, more vigorous and had more foliage than the trees on the gravelly soil. The more vigorous trees on the better soil carried far more fruit and a far greater proportion of fruit to the marketable stage, than the trees on the poorer gravelly soil. The good trees still had some fruit with dry stalks, which failed to develop normally, but they were fewer in number than in the poorer trees on gravelly soil. Application of large amounts of organic mulch to the drip zone, plus moving the irrigation sprinklers towards the drip zone were recommended to improve the soil and root health of the trees on the gravelly soil. It is expected that these measures will improve the health and vigour of the trees on the gravelly soil and consequently result in fewer poorly developed fruit with dry stalks and a greater proportion of marketable fruit.
Hibiscus viruses
Peter Stephens, a plant pathologist with NAQS, found a hibiscus rosa-sinensis at Oenpelli with virus-like symptoms of stunting and failure to produce flower buds. John Thomas from QDPI&F detected hibiscus virus S (HVS), a tobamovirus, in samples from this plant. HVS was previously found and named from its occurrence in Singapore. Hibiscus cv. "Snowflake" was inoculated at Berrimah with this Oenpelli virus by mechanical inoculation of leaf samples. The inoculated plants displayed the same symptoms of stunting and failure to produce flower buds compared with control plants.
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Photograph courtesy of Dr Peter Stephens
Figure 1. Hibiscus cv. Snowflake inoculated with HVS (left) compared with control (not inoculated) (right)
Since kenaf (Hibiscus cannabinus) was listed as a host of HVS by Singapore researchers, two sets of kenaf were inoculated with samples from the hibiscus "Snowflake", and two sets were retained as negative controls. One set of positive and negative plants were harvested when young and the other set was harvested when old. At harvesting time, leaf samples of inoculated leaves and new growth were sent to TASAG, the Elisa and Pathogen Testing Service, Department of Primary Industries, Water and Environment, Tasmania, for detection of the virus. Roots and shoots of harvested plants were separated, placed in large paper bags, oven dried at 50ºC and weighed. While the experimental kenaf work was still in progress, samples were sent to Peter Cross at TASAG to confirm the presence of HVS. Surprisingly, isometric particles were detected in transmission electron microscopy rather than the expected rod-shaped particles of the tobamovirus, HVS. These isometric particles were of the hibiscus chlorotic ring spot virus (HCRSV), which is known to exist naturally in a high proportion of hibiscus plants in Australia. This virus in our inoculated kenaf may have come either from the original plant at Oenpelli or from our Snowflake hibiscus plants which the virus was passed through in our glasshouse.
For the “old kenaf”, two representative positive and two representative negative plants were chosen. Samples for electron microscopy analysis were taken from lower and upper leaves from each plant. Because inoculated plant #3, in contrast to the other inoculated kenaf plants, grew as strongly as the un-inoculated plants, an extra sample from the mid-upper leaves of this plant was sent to TASAG for electron microscope examination. On examination, Peter Cross found the rod-shaped particles of HVS. HCRSV was detected in the lower leaves of the two representative inoculated plants, but not in the fresh new growth, probably because it takes some time for the virus to accumulate in the plant tissue. In the “test run” samples where HCRSV was previously detected, the samples were from well-expanded leaves, several leaves down from the plant apex.
An average weight of 25.34 g and 4.56 g was obtained for the shoots and roots, respectively of un- inoculated plants in contrast to 9.82 g and 1.73 g for inoculated “young” kenaf plants. For the “old” kenaf 169 Resource Protection plants, the average weight for un-inoculated plants was 25.43 g and 6.6 g for shoots and roots, respectively in contrast to 7.32 g and 0.97g for inoculated plants. There was a reduction of well over 50% in each case due to inoculation. Because we found that we were dealing with a mixed virus situation, it cannot be concluded experimentally whether the weight losses were due to HVS or HCRSV. However, inoculated “old kenaf plant” #3 which contained particles of HVS and not HCRSV was the same height as the un-inoculated control plants, whereas the inoculated “old kenaf plants” found to contain the isometric particles of HCRSV were greatly reduced in size. Thus, it can be deduced that the weight reductions in inoculated kenaf plants were due to the presence of HCRSV and not to the presence of HVS. In contrast, the marked changes in appearance of the Hibiscus rosa-sinensis (stunted plants and lack of flower buds) would seem to be due to HVS.
PROJECT: Plant Disease Reference Collection and Database
Project Officers: R. Pitkethley and L. Ulyatt
Location: Darwin
Objective:
To build and maintain the plant disease reference collection and associated database as a diagnostic tool and as a reference source.
Background:
The plant disease collection is an essential reference tool for diagnosis. Specimens of new diseases, or specimens representing new localities, are added to the collection. The specimens form the evidential basis of the plant disease database, which itself is used as a diagnostic tool and as an information source for market access and pest risk analyses.
In 2003-04 a project to link the NT plant disease database to the Australian Plant Pest Database (APPD) was initiated. The favoured option was to use the KE-Emu ® database software, which is used at Indooroopilly, Queensland by connecting to the dedicated server at Indooroopilly which in turn would be linked to APPD.
Results:
There were 59 new accessions added to the disease collection in 2004-05, bringing the total accessions to 3604.
The connection of the NT plant disease database to the dedicated server at Indooroopilly is yet to be achieved and has been delayed pending the installation and commissioning of the dedicated server.
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PROJECT: Assessment and Pathogen Testing for the Nursery Industry Accreditation Scheme Australia (NIASA)
Project Officers: A. Daly and M. Connelly
Location: Darwin and Katherine
Objective:
To assess the pathogen status of nurseries for the purpose of accreditation under NIASA.
Background:
Nurseries in the Darwin and Katherine areas are assessed for the possibility of accreditation or for continuation of their accredited status. Samples of soil, potting media and plant material are collected for pathogen testing at the Berrimah laboratory.
Results:
• Five nurseries were surveyed.
• Five samples were collected and tested for the target pathogens Phytophthora and Pythium spp. according to the “NIASA best practice guidelines”. One sample tested positive for a Pythium sp.
• Five samples were collected for identification of foliage diseases. Three palms were found infected with Bipolaris sp. The other two plants were affected by disease of a non-pathological nature.
PROJECT: Grapevine Leaf Rust (GLR) – Molecular Characterisation, Host Range and Biological Studies
Project Officers: A. Daly, C. Hennessy, R. Pitkethley, G. Schultz and G. Hore
Location: Darwin
Objective:
To develop a PCR based assay for identification of the GLR pathogen, P. euvitis, to determine its native host range and to monitor sentinel vine canopy temperature, leaf wetness and relative humidity and their relation to GLR if present.
Background:
Following the detection of GLR in Darwin, the Primary Industries Ministerial Council (PIMC) agreed to an eradication program conditional on industry support for research, replacement grapevines and communication and public relations assistance. PIMC requested that industry undertake research to identify immune or resistant cultivars that would be suitable for the practices in which they are currently used in Darwin. It was the view of PIMC that replacement grapevines were a critical component of the effective ongoing bio-security management in the region. This was the focus of the initial research conducted on the disease. In addition, it is important that the capability to identify the disease is improved using DNA analysis and that the full host range and vine canopy climate characteristics conducive to infection are understood. The Scientific Advisory Panel (SAP), formed to oversee the eradication and research programs, has guided
171 Resource Protection the direction of the research to ensure that the appropriate knowledge for protection of the wine and grape industries is generated.
The primary use of grapevines in Darwin is to supply leaves, which are used in Greek style food.
Results:
PCR based assay
The DNA analysis of P. euvitis, which is being conducted currently, is an important step in the identification of the pathogen. This is primarily due to the existence of two other closely related Phakopsora spp. which are very similar morphologically and infect species of Parthenocissus and Ampelopsis (also in the Vitaceae family), respectively. Also, there is evidence to suggest that a second species of Phakopsora (P. uva) that can infect Vitis spp. occurs in North America. Finally, P. euvitis’ host range was thought to be restricted to Vitis spp. until it was recently discovered during research in Darwin that it could infect two species of Ampelocissus native to the Top End.
The development of a PCR based assay may also lead to future work on a molecular test that can be used to distinguish different races within P. euvitis. Differences that exist might relate to higher/lower virulence, varying host range and make it possible to determine the origin of any future incursions. Purified DNA of P. euvitis as well as that of two other Vitaceae rusts, P. ampelopsidis and P. vitis, has been obtained from Japan for comparison of the DNA with that extracted from samples of the local population.
Native host range
This aspect of the research was focussed on obtaining plants from all known Australian native Vitaceae to test the leaves in vitro for susceptibility to P. euvitis. There are in the order of 30 species within five genera known to occur in Australia. It is important to determine the native host range in order to quantify the potential risk these plants pose to the southern grape growing areas by providing a “corridor” through which the disease could spread. However, prior to the work beginning, the eradication program achieved a sampling round in which there was no rust detectable in the field. Hence it was considered an unacceptable quarantine risk to continue research using live rust.
GLR was found to be pathogenic to Ampelocissus sp. under natural conditions during a small field trial at Berrimah Farm in 2004 The area was subsequently burnt as part of normal practice; however as a follow up to this trial many of the previously infected plants were re-sampled during the next wet season’s growth. No infection was present, indicating that GLR is unable to survive on plants without above ground, actively growing tissue.
Temperature, leaf wetness and relative humidity
Data loggers to measure these variables were placed in the canopy of four grapevines in suburban yards. Additional data loggers were also placed in the canopy of six native grapevines growing in remnant vegetation at CSIRO, Berrimah. The data will be used to correlate with laboratory-generated data to determine what periods of the year are likely to be the most conducive to disease and to determine differences between the native and the cultivated vines. This may explain why the rust does not readily infect native vines under natural conditions of spread.
Mass screening of commercial cultivars and local household vines
Seven more varieties of Vitis sp. were obtained from CSIRO, Merbein in late 2004 for resistance screening. All were found to be of moderate to high susceptibility.
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Testing of household vines has also ended due to the absence of GLR in the community. In total, samples from 100 vines were tested; 91 were found to be moderately to highly susceptible. The other nine samples did not survive long enough in vitro to give a result.
Fungicides
Testing fungicides for their eradicative/curative ability in controlling GLR was completed. This involved inoculating leaves with the rust five days prior to application of the fungicide (as opposed to the protective assessment where the leaves were inoculated after application of the fungicide). The tested fungicides and their effects are presented in Table 1.
Table 1. The fungicides tested and their effect
Trade name Active ingredient Disease control Alto Cyproconazole Effective Bayleton Triadimefon Ineffective Bogard Difenconazole Moderate Domark Tetraconazole Moderate Folicur Tebuconazole Effective Impact Flutriafol Ineffective Marvel Benomyl Ineffective Plantvax Oxycarboxyn Effective Scala Pyrimethanil Moderate Tilt Propiconazol Ineffective Vision pyrimethanil and fluquinconazol Ineffective
NB. Table 1 shows that three fungicides, Alto, Folicur and Plantvax were effective in eradicating the rust after it has infected the leaf, some sporulation of the disease still occurred, that is, no fungicide was 100% effective during this assessment. Due to the quarantine risk posed by research activities, testing the effectiveness of fungicides by spraying whole plants infected with the rust to verify the results could not be carried out.
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PROJECT: A Management System for Diseases of Mangoes – Post Harvest Storage Diseases
Project Officers: S. Bhuiyan, M. Boyd, B. Condé and R. Pitkethley
Location: Katherine
Objectives:
To determine disease occurrence in mangoes sea-freighted at ambient temperature (23ºC).
To assess the longevity of fruit at 13ºC during sea-freight.
To identify the general problems associated with post-harvest treatments, packing and handling.
To identify the causal organisms associated with post-harvest diseases of mangoes.
Background:
Mango production is a fast growing industry in Australia, resulting in a rapid saturation of local markets. Recent research indicated that mangoes can be stored for up to six weeks by lowering the temperature (to o ~13 C) and O2 level, and increasing CO2 of the surrounding atmosphere. Shipping containers equipped with controlled atmosphere (CA) technology have opened a window of opportunity for Australian mangoes to be sent to distant overseas markets at relatively low cost. The performance of each consignment depends on infection and inoculum levels associated with exported fruit.
Post-harvest diseases are the main constraints to long term storage, as well as for transport to overseas markets. Mangoes grown in Katherine are believed to be relatively free of diseases due to dry and warm weather conditions, and have the potential to be well received in overseas markets.
The objectives of the study are to determine the post-harvest diseases and their causal organisms on fruit maintained at sea-freight temperature (13oC); to determine the effects of picking (harvesting) time on the incidence of post-harvest disease; and to develop a grading system to identify export management needs for sea-freight mangoes.
Method:
First pick trial
Sixteen growers participated in the first pick trial by providing three boxes of fruit each. Each box contained approximately 17 export grade mangoes. Out of three boxes, one box was maintained at 23oC (control) and two boxes at 13oC. Fruit was inspected at weekly intervals up to three weeks from harvest at 23oC (when fruits became unsuitable for consumption) and for five weeks at 13oC. A total of 829 fruits were visually assessed for post-harvest disease incidence. Causal organisms of fruit infections were determined by standard laboratory procedures.
Second pick trial
Seven growers, including six from the first pick trial participated in the second trial. The trial was conducted two weeks after the first pick trial, and trial procedures were the same as for the first trial. A total of 268 fruits were assessed for post harvest disease incidence.
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Comparison of picking times
Since six growers participated in both the first and second pick trials, a comparison could be made between two picking times to determine changes in disease incidence from the first to second pick.
Development of a grading system
Based on disease incidence (%) on fruit at weeks 4 and 5, stored at sea-freight temperature (13oC), a grading system was developed to assess the export management needs of sea-freight fruit.
Results:
Disease incidence at 13oC
All fruit from the first pick, which was maintained at 13oC, remained free of post-harvest diseases for up to three weeks and became 16.67% infected after five weeks, whereas fruit maintained at 23oC had 21% disease incidence after three weeks (Table 1). Fruit from the second pick also had similar disease patterns.
Comparison of pos- harvest disease between first and second pick trials
There was an approximately two to five-fold increase in disease incidence in second pick fruit compared with first pick fruit (Table 2). This strongly suggests fruit from the first pick was a better candidate for export by sea-freight.
Table 1. Post-harvest disease incidence (%) in first pick sea-freight mangoes maintained at 13oC and 23oC
Week Incidence(%) at 13oC Incidence(%) at 23oC 1 0 0 2 0 11.20 3 0 21.43 4 5.33 - 5 16.47 -
Table 2. Post-harvest disease incidence in first and second pick mangoes maintained at 13oC for five weeks
Grower 1st pick 2nd pick Change (times) Incidence (%) Incidence (%) 1 2.33 12.5 5.36 2 0 16.67 - 3 10.71 28.57 2.67 4 10 33.33 3.33 5 0 37.50 - 6 29 50 1.72
Grading
Fruit which had 10% or less disease incidence after four weeks at 13oC was exportable using various management options depending on their performance at week five. Fruit with more than 10% disease incidence was not suitable for export; a comprehensive management strategy was suggested to overcome the disease problem.
Disease incidence
Approximately 30% to 35% of fruit was affected by stem end rots, whereas 8% to 15% of fruit was affected by anthracnose (Table 3). Only 1.3% to 1.44% of fruit had stem end rot and anthracnose at the same time.
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The relatively low incidence of anthracnose on fruit may be due to high temperatures and low relative humidity during the mango-growing season in the Katherine region.
Table 3. Incidence (%) of stem end rot (SER) and anthracnose in mangoes maintained at 23oC and 13oC
Temperature SER Anthracnose SER+ (%) (%) Anthracnose(%) 23oC 30.05 8.47 1.30 13oC 35.33 15 1.44
Causal organisms
The highest incidence of causal organism associated with post-harvest disease in mangoes was Dothiorella ‘long’ (43%) followed by Alternaria alternata (15%), Colletotrichum gloeosporioides (11%) and Dothiorella dominicana (10%).
D. ‘long’ is a relatively new organism which causes SER and has not been reported anywhere in the world except in Australia. It has never been considered a major cause of post-harvest disease elsewhere in Australia. The biology, ecology and epidemiology of the organism have not been studied. Another interesting finding is the relatively high incidence of A. alternata in sea-freight mangoes. Disease due to A. alternata occurred when both C. gloeosporioides and Dothiorella spp. were well controlled by chemical applications or harsh and dry environments. A. alternata is considered to be an important post-harvest pathogen of mangoes in Israel. Further investigations are needed to understand the biology and ecology of D. ‘long’ and A. alternata in order to develop an effective management strategy.
For further details please contact the senior author.
PROJECT: Management Systems for Diseases of Asian Vegetables
Project Officers: B. Condé and I. Arao-Arao
Location: Darwin
Objective:
To develop a management system for diseases of Asian vegetables.
Background:
Since the late 1980s, Asian vegetables grown by farmers of Vietnamese and other Asian descent have dominated the vegetable industry in the Darwin rural area. This has increased demand for diagnostic services and for the development of improved practices for disease management for this sector. In addition to the steps reported below, a project is in progress to develop a management system for Fusarium wilt of snake beans. This is reported separately.
Method and Results:
Tomato
Leaf roll Since tomato leaf roll disease which is caused by the tomato leaf curl geminivirus (TLCV-Au) was discovered in the NT in 1970 it has always shown a sigmoidal curve of incidence with high levels of disease early in the
176 Technical Annual Report 2004-05 year, levelling out to very low levels mid-way through the dry season. However, in 2004, a farmer reported significant levels of the disease in his late season crop. TLCV-Au was confirmed by Dr Ali Rezaian, CSIRO Adelaide in samples taken on 6 October 2004. This was coincidental with the presence of a large number of sweet potato whiteflies (Bemisia tabaci), which were confirmed by Dr Robin Gunning, NSW Agriculture, Tamworth as B-biotype.
Bacterial wilt The Dutch vegetable seed company Enza Zaden requested us to coordinate a tomato bacterial wilt screening trial between it and a Darwin grower. Jacqueline Nieuwenhuis, the laboratory manager and plant Breeder at Narromine, visited Darwin on 18 May 2005 to plant the trial crop with the grower. As the plants matured, we monitored them with the grower for symptoms of bacterial wilt.
Basil
With increasing problems in sweet basil production due to Fusarium wilt and base rot, there has been renewed interest in the use of Nufar F1 sweet basil as a component in a management strategy. Plant Pathology obtained seed of lemon basil after reports suggested it had a high degree of resistance to basil Fusarium wilt and base rot.
Circular leaf spot of sweet basil (Cercospora guatemalensis Mueller and Chupp) was a problem towards the end of 2004 with the onset of humid weather. Chlorothalonil with a seven-day withholding period and copper fungicides with a one-day withholding period were recommended to control this cercospora leaf spot.
Cowpea virus
An investigation identified a cowpea mosaic virus which affected two plants of PI 162-925 in the Plant Pathology garden. It was very easily transmitted by mechanical inoculation. In experimental inoculation and indexing tests it was found to infect four cowpea lines: Arafura, Iron, Borroloola, and CB5. Eden cowpea and green pod Kaohsiung snake beans were resistant (immune) to systemic infection by the virus. The virus caused a variety of symptoms in the cowpeas that we inoculated ranging from a faint specking in Iron through a strong mottle in PI 162-925 and mosaic in CB5 to a hypersensitive reaction in Borroloola with leaves turning yellow, dropping off and plants dying. Initial tests on PI 162-925 indicated no seed transmission in 83 seeds tested. Further investigations including work on the host range, transmission, seed transmission tests and identification are continuing.
Other vegetables
Tomato spotted wilt virus on lettuce, spread by tomato thrips (Frankliniella schultzei), was recorded for the first time in the NT in Alice Springs.
Investigations were made into lettuce problem in Alice Springs. No evidence of disease was found.
Severe rust coloured blotching on taro leaves on a commercial property were symptoms of severe oedema.
Phytoplasma diseased samples of snake beans, eggplants and tomatoes were investigated by Claire Steten and Lucy Tran-Nguyen in Karen Gibbs’ laboratory at Charles Darwin University. The disease was caused by tomato big bud phytoplasma.
Several samples of Cercospora citrullina on watermelon and Cercospora cruenta on snake beans were diagnosed and treatment was recommended.
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PROJECT: A Management System for Fusarium Wilt of Snake Beans
Project Officers: B. Condé and I. Arao-Arao
Location: Darwin
Objective:
To develop a management system for Fusarium wilt of snake beans.
Background:
Fusarium wilt of snake beans which is caused by Fusarium oxysporum f.sp. tracheiphilum (Fot), was first detected in the NT in Darwin in 1999. The value of the snake bean industry had reached $2 million before the impact of Fusarium wilt. The disease has seriously affected the industry.
In early work we found that there are three strains of the pathogen in the Darwin area which can be differentiated on culture characteristics including colour. Experiments in 2001-03 showed that the three strains belonged to three different vegetative compatibility groups (VCG). In the work reported below, the three strains are represented by the isolates 24946 (the original, 'plum' coloured isolate), 26536 (white) and 26571 (pink).
Method and Results:
Races, VCG and strains of Fot
Six sets of snake bean and cowpea samples were processed for Fusarium wilt from the field in 2004-05. The pink strain was isolated from green pod Kaohsiung (GPK) snake beans, from a property in Webb Road Humpty Doo. Plants of GPK snake beans strains from Jefferis Road and a second property in Webb Road were infected with pink and white strains at both properties. A later sample from the second Webb Road property yielded a mixture of plum and pink strains from one plant. This was noteworthy in that it was the first time that the plum strain was isolated from the field since 1999. A wilted Borroloola edible-podded cowpea from Leanyer yielded the white strain, while the pink strain was obtained from local purple snake beans from the same property.
Screening for resistance
Eden cowpea was screened and found to be susceptible to all three strains. Eden plants were more susceptible than GPK because they showed symptoms faster than GPK. As such, Eden was useful for passaging all three strains for maintenance and multiplication of the isolates. Theo Aniceto snake bean was screened against all three strains. It showed some resistance to the white strain. Cowpea 40323 showed some resistance to plum Fot. Seed from a commercial pack of black eye beans was sown. Seed from two of the resulting plants was multiplied and labelled #1 and #2. Plants grown from these two lots of seed were screened against the three strains. Plants from #2 were resistant to the plum stain, but plants from #1 were susceptible, indicating that this commercial seed lot was composed of different black-eye varieties.
The edible-podded cowpea, Borroloola was screened against white Fot, to which it previously tested resistant. This time Borroloola screened as susceptible to white Fot (but with a moderate to high degree of resistance). Two cowpea lines, Mississippi cream and Alf Cameron brown seeds were again screened for reaction to white Fot, and both were confirmed resistant. The only lines testing resistant to all three strains were Iron, Arafura, Alf Cameron old brown type and Mississippi cream - all cowpea types.
178 Technical Annual Report 2004-05
Breeding for resistance
A bulk screening of 344 plants of a bc2F1 generation obtained from the cross Arafura x GPK for resistance to isolate 26536 was commenced in the last financial year. All 344 plants tested susceptible to white Fot. Together with the 33 individual plants multiplied clonally and found to be susceptible, a total 377 plants of this cross were found to be susceptible to white Fot. Previous investigations of the parents, F1 and the bc1F1 plant #2-2, had demonstrated repeatedly that the cowpea parent was resistant. It was also suggested that the F1 and bc1F1 plant #2-2, both of which were tested as clonal material were also resistant to white Fot. It was hypothesised that the resistance in Arafura is dominant. When a resistant bc1F1 plant #2-2 with dominant resistance was backcrossed with a susceptible GPK, it was expected that the resulting bc2F1 population would consist of equal numbers of resistant and susceptible plants. This was not so. All 377 bc2F1 plants were susceptible to white Fot. This strongly suggests that the bc1F1 plant #2-2 selected for use as the resistant plant for further breeding purposes, was able to escape disease, but was not a genetically resistant plant.
The bc1F1 plant #2-2 (as clonal material) was screened again against plum, pink and white Fot and was found to be susceptible to all three strains. However, clonal material of F1 (from the cross Arafura x GPK) also screened as susceptible to all three strains. In the past, this F1 material screened resistant to all three strains. Two comments can be made here. This screening would appear to have been more rigorous than the previous one. Secondly, clonal material may be much more susceptible to infection by Fusarium wilt than material grown directly from seed, so that it is possible that genuinely genetic resistant material might appear to be susceptible. To this end, clonal material of the line PI 162-925 was inoculated with white Fot. This rapidly wilted and died and white Fot re-isolated from affected plants. Many pots of this line were grown for virus experiments, and none became infected with Fot, whereas many nearby pots of Eden or CB5 cowpea died from Fusarium wilt. PI 162-925 plants derived from seed will be inoculated with white Fot and reported in the next Technical Annual Report. Also, it is planned to do comparative screenings for Fusarium wilt resistance of all four resistant cowpeas, Iron, Arafura, Alf Cameron old brown type and Mississippi cream as seedlings compared with clonal material to determine if the type of material influences the resistance reaction.
Breeding has continued with production of three more F1 hybrids in 2004-5, involving crosses of GPK with the resistant cowpeas, Iron, Mississippi Cream and with Alf Cameron old brown type. Breeding involving the cross GPK x Borroloola was discontinued because this cowpea parent was found to be only partially resistant to the white strain. Also, breeding was continued with the cross, Arafura x GPK to produce more bc1F1 seed by back-crossing the F1 plant onto GPK. Screening of a large population of F2 plants from the cross GPK x Iron is in progress. The ratio obtained here should enable us to hypothesise on the genetics of resistance to white Fot in Iron. Another F2 population (GPK x Iron) is being screened against a composite of all three strains in case we need to use an F2 plant to progress the breeding. At present, further breeding work is on hold until some screening and genetic issues are sorted out, such as are clonal material (cuttings) of resistant plants susceptible to Fusarium and what are the genetics of resistance for the particular cowpea and strain of Fusarium wilt.
Control of Fusarium wilt
Many farmers are no longer growing snake beans. Some plant beans on new blocks to try to avoid the disease. Some are grafting snake beans onto resistant cowpeas as discussed in the 2003-03 Technical Annual Report, and some are trying one of the moderately resistant varieties, “Bat Kong”. Some are trialling F2 plants derived from the cross GPK x Borroloola in cooperative work with Stuart Smith of Elders Darwin.
179 Resource Protection
PROJECT: Management of the ‘Tropical’ Race 4 Strain of Banana Fusarium Wilt
Project Officers: A. Daly, G. Walduck, C. Kelly, R. Connelly and A. Wilson
Location: Darwin
Objective:
To identify banana varieties with resistance/tolerance to tropical race 4 Fusarium wilt and conduct other studies associated with the management of the disease.
Background:
The detection of tropical race 4 of Fusarium oxysporum f. sp. cubense (Foc), a disease for which there is no means of effective chemical control, in several localities in Darwin's rural area since 1997 highlighted the need to seek sources of resistance to the pathogen and assess ways in which the disease can be better managed. A site at the Coastal Plains Horticultural Research Farm, gazetted as the Coastal Plains Banana Quarantine Station, was built and artificially infected with the soil-borne disease. The response of a number of different varieties is currently being assessed. The varieties have been planted in four stages (batches). Assessment of Batch 1 is already complete. Assessment is continuing with Batches 2A (planted in 2002), 2B (planted in 2003) and 3 (planted in 2004). Management options for the disease are being investigated at commercially producing properties as well as the testing facility at Coastal Plains.
Results:
Details of the varieties currently under assessment are presented in Table 1.
Table1. Banana varieties currently assessed
Variety Batch Genome Type FHIA 23 (hybrid) 2A AAAA Dessert Mutiara E 2A AAB Dessert Novaria D (Cavendish) 2A AAA Dessert Novaria G (Cavendish) 2A AAA Dessert Pisang Embun 2A AA Dessert Pisang Jari Buaya 2A AA Dessert Ducasse 2B ABB Dessert/cooking Grand Nain (Cavendish) 2B AAA Dessert Improved Lady’s Finger 2B AAB Dessert Pacific Plantain 3 AAB Cooking Pisang Celan 3 AAB Dessert GCTCV Formasana (Cavendish) 3 AAA Dessert D5 (ex South Africa) 3 AAA Dessert DPM25 (ex South Africa) 3 AAA Dessert PKZ (ex South Africa) 3 AAAB Dessert RSS3 (ex South Africa) 3 AAA Dessert
Data generated so far for varieties in Batches 2A and 2B indicate a high degree of susceptibility in both the plant crop and the ratoon crop cycles for all but one variety, Pisang Jari Buaya (Table 2). This variety however is showing a higher susceptibility in the ratoon cycle than in the plant crop cycle. On-going assessment will determine if this trend continues.
Varieties in Batch 3 were planted early in 2004 and so far are showing a 100% infection rate in all replicates. Almost all plants have failed to make it to bunch emergence. 180 Technical Annual Report 2004-05
Disease ratings of all varieties made in the field are backed up by laboratory testing of selected plants in each replicate to confirm the presence of an infection of Foc ‘tropical’ race 4.
A summary of the results of screening plants in Batch 2 is presented in Table 2.
Table 2. Screening results for banana varieties
Variety Plant crop (at Aug 2002) Ratoon 1 (at June 2003) Infected Rateable plants Infected Rateable plants Mutiara E 30 30 28 28 Novaria D (Cavendish) 29 30 29 29 Novaria G (Cavendish) 30 30 27 27 Pisang Embun 30 30 30 30 Pisang Jari Buaya 0 30 12 29 Grand Nain (Cavendish) 26 30 26 26
Other work being done concurrently aims to better manage the disease whilst resistant varieties are being sought. The assessment of the temperature/time relationship during the hot water treatment for sanitation of Foc ‘tropical’ race 4 infected plant tissue and subsequent advice given to farmers following the results has led to one farmer adopting a burning policy for any newly infected plants occurring on the property. The technique involves surrounding the infected plant with a heat shield (corrugated iron) and creating an intense fire to burn the plant where it stands. Important in the technique is leaving the plant standing so that there is minimal disturbance of the site and the pathogen inoculum within the plant. Fuel (wood) must also be continually supplied to the fire to keep it burning until all of the plant parts have been “cooked”. There is strong anecdotal evidence to suggest that the practice has led to a marked decrease in the infection rate in the plant crop by limiting the spread from plant to plant to almost nil. Further research will be conducted to determine the depth of subterranean heat transfer and the temperatures achieved. This will hopefully determine how effective the practice is at reducing pathogen levels within the soil.
A commercial formulation of Trichoderma (well-known broad spectrum mycoparasite/biocontrol agent) has been used to determine whether it can offer a level of protection to a new planting of banana tissue culture on a commercially operating property. The formulation has been applied as a drench to each plant in selected rows fortnightly since planting during the second half of last year. However, at this stage the treated rows are showing a disease incidence similar to the untreated rows. The rate of infection in all plants continues to steadily increase.
181 Resource Protection
PROJECT: Management System for Diseases of Cotton in the Katherine Region
Project Officers: S. Bhuiyan, M. Boyd and C. Martin
Location: Katherine
Objectives:
To determine the effect of foliar application of potassium on development of alternaria leaf spot of cotton
To determine the effect of chemical fungicides on development of alternaria leaf spot of cotton
Background:
Although alternaria leaf spot is considered to be a minor disease of cotton (Gossypium hirsutum) in southern Australia, it appears to be of major importance in northern Australia. It has been a major problem of cotton in the Katherine (NT) and Kununurra (WA) regions for several years. There are reports of high disease incidence in the Burdekin region of Queensland. Both Alternaria macrospora and A. alternata are implicated as the causal organism of the disease. In Zimbabwe, it was reported that potassium (K) deficiency during growth and flowering predisposed cotton plants to alternaria leaf spot. It is believed that cotton plants become deficient in K during flowering and boll formation. Foliar application of K at flowering and afterwards may reduce the K deficiency level as well as alternaria leaf spot on cotton. Chemical fungicides are being used elsewhere to control various leaf diseases.
Method and Results:
Effects of foliar K
An experiment was undertaken at the Katherine Research Station on three randomly selected replicated plots (9 m x 50 m each). KNO3 was applied at the rate of 13 kg/ha with the help of a boom sprayer. The first application was conducted approximately seven days before flowering and the following three applications after flowering at two weeks interval. Three unsprayed plots were used as controls.
Ten randomly selected plants from each replicate were marked with spray paint. The plant next to the painted plant was selected for assessment of disease incidence and severity. Main stem leaves at three canopy levels (1-7 nodes, 8-14 nodes, and 15+ nodes) were assessed visually for disease incidence and severity. A modified visual scale was used for the assessment of severity of alternaria leaf spot. Assessments were conducted weekly between July and September, 2004.
Disease incidence
There were no significant differences in disease incidence between sprayed and unsprayed plots (data not presented). Most of the leaves became infected with alternaria two to three weeks after the first assessment.
Disease severity
Disease severity was higher at the middle canopy level (8-14 nodes) in both sprayed and unsprayed plots (Figure 1). Significant differences in severity between sprayed to unsprayed middle canopy levels were observed from late July to the third week of August. There were no significant differences in disease severity between sprayed and unsprayed plots at the 1-7 or 15+ nodes canopy level.
182 Technical Annual Report 2004-05
Heavy overnight dew on middle canopy leaves and associated cooler night temperature in June, July and August may have predisposed middle leaves to leaf spot disease. Due to continuous development of new leaves on 15+ nodes canopy levels, the overall severity of disease on top leaves was less. Likewise, lower canopy leaves had relatively less exposure to heavy dew, thus disease severity was less.
Sprayed/Bottom 20.00 Unsprayed/Bottom Sprayed/Middle Unsprayed/Middle Sprayed/Top 15.00 Unsprayed/Top
10.00 M ean Incid
5.00
0.00 2-Jul 12-Jul 22-Jul 1-Aug 11-Aug 21-Aug 31-Aug 10-Sep 20-Sep 30-Sep
Figure 1. Severity of alternaria leaf spot over time at various canopy levels after spraying with foliar K
Leaf shedding
Leaf shedding was higher in the middle canopy level (8-15 nodes) in both sprayed and unsprayed plots (Figure 2). Significant differences in leaf shedding were observed between sprayed and unsprayed plants in the middle canopy level from the last week of July to the third week of August. There were no significant differences in leaf shedding severity between sprayed and unsprayed plots at 1-7 or 15+ nodes canopy level.
8
Sprayed/Bottom 7 U nsprayed/Bottom Sprayed/Middle 6 Unsprayed/Middle Sprayed/Top 5 U nsprayed/Top
4
3
Num ber of Le Num of ber 2
1
0 2-Jul 12-Jul 22-Jul 1-Aug 11-Aug 21-Aug 31-Aug 10-Sep 20-Sep 30-Sep
Figure 2. Shedding of leaves over time due to alternaria leaf spot at various canopy levels after spraying with foliar K
183 Resource Protection
Fungicide trial
Three fungicides from two groups were used:
- Dithane Rainshield 750 (Mancozeb) - Score 250EC (Difenoconazole) - Folicur 430SC (Tebuconazole)
Spray applications were conducted as follows
- Dithane (2 kg/ha) + Score (500 mL/ha) - Folicur (250 mL/ha) + Agridex (1 L/ha)
• Dithane (2 kg/ha) + Score (500 mL/ha)
- Three spray applications (May 7 to May 31) - Two-week intervals
• Folicur (250 mL/ha) + Agridex (1 L/ha)
- Six application (June 15 to August 20) - Two-week intervals
No significant differences were observed between sprayed and unsprayed plots in alternaria leaf spot disease incidence (Figure 3).
120
100
80
Sprayed 60 Unsprayed Incidence
40
20
0
4 4 4 04 04 04 04 004 004 /20 /20 /20 2 /2 9/ /0 /09 1/07/20 8/07/200 4/08/200 1/08/200 8/08 5/08 1/09 8 5 07/07/2004 14/07/2004 2 2 0 1 1 2 0 0 1 Date
Figure 3. Effects of fungicides application on incidence of alternaria leaf spot in cotton at Katherine Research Station, 2004
184 Technical Annual Report 2004-05
Significant differences in leaf spot disease severity were found between sprayed and unsprayed plots (Figure 4) during the whole trial period.
18
16
14
12
10 Sprayed Unsprayed
Severity 8
6
4
2
0
4 4 4 04 04 04 04 004 004 /20 /20 /20 2 /2 9/ /0 /09 1/07/20 8/07/200 4/08/200 1/08/200 8/08 5/08 1/09 8 5 07/07/2004 14/07/2004 2 2 0 1 1 2 0 0 1 Date
Figure 4. Effects of fungicide application on severity of alternaria leaf spot in cotton at Katherine Research Station, 2004
Acknowledgement
Financial assistance was provided by the Cotton CRC.
PROJECT: National Grapevine Leaf Rust Eradication Program (NGLREP) – Pathogen Testing Service
Project Officers: A. Daly, R. Pitkethley and C. Hennessy
Location: Darwin
Objective:
To provide NGLREP with a diagnosis of the disease status of grapevine specimens submitted during the program and preservation of the specimens in the Plant Pathology and Mycology Herbarium.
Background:
Following the detection of the exotic disease grapevine leaf rust (GLR), caused by the fungal pathogen Phakopsora euvitis, in urban Darwin in 2001, NGLREP was initiated to remove all infected vines (Vitis spp.) with funding from the Commonwealth and State governments.
185 Resource Protection
Leaf specimens from properties in Darwin, Palmerston and rural areas (including Katherine) are submitted almost on a daily basis during the program to determine if they were infected with GLR. Grapevines confirmed to be infected are subsequently removed from the property of origin. Specimens of the native grapevine species Ampelocissus acetosa and A. frutescens are also collected for analysis from plants in close proximity to areas where GLR has occurred. These plants were included in the survey following the discovery during laboratory experiments that they were susceptible to the rust. Infected specimens collected during the program are pressed, dried and stored in the herbarium for future reference if required.
Results:
• The eradication program commenced the ninth round of testing just in late June 2005 when approximately 176 vines remained in the quarantine area (50 km radius from the CBD).
• There were 928 specimens of Vitis spp. examined.
• Nine (1%) Vitis spp. were infected with rust (Phakopsora euvitis).
• There were 38 (4%) Vitis spp. infected with grapevine downy mildew (Plasmopara viticola).
• There were 45 (5%) Vitis spp. infected with grapevine powdery mildew (Oidium sp.).
• There were 172 specimens of Ampelocissus spp. examined.
• One Ampelocissus sp. was infected with rust (Phakopsora euvitis). This was the first recorded natural infection of this species by GLR.
PROJECT: Survey for Banana Leaf Spot Diseases
Project Officer: A. Daly
Location: Darwin
Objective:
To survey and collect leaf spot disease samples in bananas and submit them to QDPI&F for identification to ensure freedom from Black Sigatoka disease.
Background:
As part of the national surveys for detection of Black Sigatoka, leaf samples infected with various diseases are collected from commercial plantations as well as residential dwellings in Darwin and the rural area and forwarded to QDPI&F Mareeba for identification of the pathogen. Some leaf spot diseases are not readily distinguishable from Black Sigatoka in the field.
186 Technical Annual Report 2004-05
Results:
• Twenty five samples were collected from six localities. The localities included three commercial properties, Coastal Plains Horticulture Research Farm, a rural residential property and Pine Creek
• The causal organisms of the various leaf spots collected were:
Cladosporium musae Cladosporium sp. Cordana musae Deightoniella torulosa Mycosphaerella musae Mycosphaerella musicola Periconiella musae Veronaea musae
None of these leaf spots were caused by banana black Sigatoka.
187 Resource Protection
SERVICE: PLANT HEALTH (PROTECTION)
Program: Plant Health (Protection)
PROJECT: Exotic Cryptotermes Termites
Project Officers: B. M. Thistleton, G. R. Brown, M. Neal and L. Zhang
Location: Darwin and Nhulunbuy
Objective:
To detect, identify and manage exotic termite incursions.
Background:
Within the last 10 years there have been three incursions of the exotic dry wood termite, Cryptotermes dudleyi Banks (Isoptera: Kalotermitidae) in Darwin. Two of these have been in displays at the Museum and Art Gallery of the NT which have been successfully eradicated under the Australian Quarantine and Inspection Service (AQIS) supervision. The third incursion is in a house at Nightcliff which has been treated twice, but it is unknown if this infestation has been completely eradicated. The origin of these incursions is unknown.
Exotic termites of the genus Cryptotermes are routinely found infesting (Indonesian) foreign fishing vessels (FFV) that are brought into Darwin and Gove Harbour. They may colonise small pieces of timber and are usually only detected after 10 or more years when they reach maturity. Those in the reproductive state are winged.
FFV are a potential source of termite incursions if mating flights occur.
Method:
Close liaison is maintained with AQIS by one author (GRB) who is currently the AQIS quarantine entomologist for the NT.
All FFV coming into Darwin Harbour are inspected by quarantine officers and are subsequently inspected by Entomology staff as required. These boats are subsequently usually burnt.
Because of the poor condition of these boats, the apparent high termite infestation rate, and the ease in which timbers can be lost overboard, a survey of Darwin Harbour foreshore between Frances Bay boat ramp and Doctors Gully, and between Stokes-Hill and Fort-Hill wharves was undertaken. Drift-wood, dead trees and tree butts were examined and termites collected for identification.
The Nightcliff incursion was monitored and found to still have active termites in February 2005.
Results:
Exotic species of termite of the genus Cryptotermes were routinely found infesting boats in Darwin and Gove Harbours, including Cryptotermes dudleyi. Detection was most frequently made on the basis of the presence of frass. On a few occasions, workers, nymphs and reproductives were found, but only rarely were soldiers found. The latter are necessary if the termites are to be identified to species level.
188 Technical Annual Report 2004-05
Identifiable termites were not often found on these boats, although there was usually evidence. This high incidence-low detection rate was confirmed on a number of occasions when boats were removed from the water to be burnt. This presented an opportunity to examine boats more exhaustively and to get a true picture of how extensively these boats are infested.
The survey of Darwin Harbour found several colonies of the native C. secundus (Hill) (Isoptera: Kalotermitidae). No exotic species were detected, but the survey was not extensive.
The incursion at Nightcliff was detected in April 2003 and was subsequently treated. The house was reinspected in February 2005 and a large active colony was found in decking. The nest was treated and the affected decking and joists were replaced.
Conclusions:
• The entry of FFV into harbour probably poses a high risk of introducing exotic species into the NT and Australia.
• Close cooperation with AQIS needs to be maintained.
• Surveys of the foreshores of Darwin and Gove Harbours need to be continued and broadened.
• The Nightcliff incursion should continue to be monitored.
PROJECT: Quarantine Entomology
Project Officers: L. Zhang and G. R. Brown
Location: Darwin
Objective:
To identify insects and other organisms intercepted in Quarantine, to provide advice on the quarantine significance of these organisms and to facilitate a database for these records.
Background:
AQIS provides partial funding for the quarantine entomologist to provide identifications on insects intercepted by quarantine in the Northern Territory.
Method:
Insect and other animal samples collected by quarantine inspectors are submitted with insect interception record sheets to Quarantine Entomology for identification and advice. The advice and identification are provided and the insect interception identification record sheets are completed and returned to AQIS for recording on the database. Identifications are recorded on the pest and disease interceptions database of AQIS in Darwin.
Interceptions that were considered to be of quarantine significance were investigated further.
Results:
During the year, 381 insect interceptions totalling 619 samples were received and recorded. Most of the samples were collected in and around Darwin Harbour (318), including moored and undocked vessels (132), East Arm Wharf (85), Perkins Wharf (75) and other unspecified various Darwin Harbour wharves and
189 Resource Protection marinas (26); Gove Harbour (148); Darwin Airport (69); AQIS Darwin office (11); RAAF Darwin (11); Groote Eylandt (8) and air cargo (Patrick’s and Australian Air Express) (8).
Species found
The following is a list of taxa and the number of samples examined:
Acarina 9 Aranaea 77 Coleoptera 152 Dermaptera 4 Blattodea 18 Diptera 80 Mollusca 21 Hemiptera 20 Hymenoptera 130 Isopoda 14 Isoptera 32 Lepidoptera 27 Odonata 2 Orthoptera 6 Pseudoscorpiones 1 Psocoptera 23 Reptilia 3
Countries of origin
The following are numbers of samples examined from each region:
Africa 1 Australia 17 Brunei 6 Bulgaria 1 China 13 Denmark 1 East Timor 47 Fiji 1 Greece 3 India 1 Indonesia 327 Italy 6 Japan 9 Malaysia 12 Mauritius 4 Myanmar 2 New Zealand 2 Papua New Guinea 1 Philippines 11 Singapore 69 South Africa 3 Spain 1 Sri Lanka 1 Thailand 7 UK 1 USA 5 Vanuatu 3 Vietnam 1 Unknown 63
190 Technical Annual Report 2004-05
Interesting records
• The following are records of exotic snails:
- Giant African snail, Achatina fulica (Bowdich) (Eupulmonata: Achatinidae), was collected on containers from Singapore and East Timor - Vermiculate garden snail, Eobania vermiculata (Müller) (Eupulmonata: Helicidae), was collected on break bulk crates from Italy - Japanese euhara snail, Euhadra sp. (Eupulmonata: Camaenidae), was collected on wooden crates form Japan - Viviparous freshwater snail, Bellamya sp. (Eupulmonata: Viviparidae), was collected in seeds from Thailand - Clayey chlorite snail, Chloritis argillacea (Férussac) (Eupulmonata: Camaenidae), was collected on containers from Singapore and East Timor - Perforated snail, Perforatella sp. (Eupulmonata: Helicidae), was collected on herb from Greece - Land snail, Hemiglypta sp. (Eupulmonata: Helicarionidae), was collected on a container from China.
• Two records of snails, suspected of being exotic, Bradybaena sp. (Eupulmonata: Bradybaenidae), were collected on containers from Singapore.
• One record of field slug, suspected of being non-indigenous and not NT species, Deroceras sp. (Eupulmonata: Agrolimacidae), was collected on cut flowers from Mauritius.
• Sixteen records of dry wood termites, Cryptotermes spp. (Isoptera: Kalotermitidae), were collected on foreign fishing vessels from Indonesia.
• One record of Dry wood termites, Cryptotermes sp. (Isoptera: Kalotermitidae), was collected in wooden craft from Fiji.
• One record of an exotic termite, Coptotermes, sp. (Isoptera: Rhinotermitidae), was collected in container from South Africa.
• One record of an exotic honeybee, Giant honeybee, Apis dorsata Fabricius (Hymenoptera: Apidae), was collected from a box from East Timor.
• Twenty-three records of exotic dengue mosquito, Aedes aegypti (Linnaeus) (Diptera: Culicidae), were collected on foreign fishing vessels from Indonesia (20) and unknown areas (3).
• One record of a nest of Crazy ants, Anoplolepis gracilipes (Smith) (Hymenoptera: Formicidae), collected on foreign fishing vessel from Indonesia.
• One record of an exotic ant, Tapinoma sp. (Hymenoptera: Formicidae), was collected on yacht from the Philippines.
• One record of a nest of Asian paper wasp, Polistes chinensis (Fabricius) (Hymenoptera: Vespidae), was collected on steel pipes from China.
• One record of exotic timber borer beetle, Dinoderus bifoveolatus Wollaston (Coleoptera: Bostrichidae), was collected on foreign fishing vessel from Indonesia.
• One record of exotic timber borer beetle, Sinoxylon conigerum Gerstäcker (Coleoptera: Bostrichidae), was collected on a foreign fishing vessel from Indonesia.
• Twenty-two records of brown widow spider, Latrodectus geometricus C. L. Koch (Araneida: Theridiidae), in/on containers from East Timor (12), Singapore (9) and Indonesia (1).
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PROJECT: National Grapevine Leaf Rust Eradication Program
Project Officers: S. West, G. Schultz, S. Hornby and G. Hore
Location: Berrimah Farm
Objectives:
To conduct surveillance for grapevine leaf rust (GLR) on all remaining grapevines within the quarantine area including Darwin, Palmerston and the greater Darwin rural area (GDRA). Additional surveillance will also be conducted outside of the quarantine area between Darwin and Mataranka on known grapevines.
To remove all vines diagnosed with the disease and revisit all removal sites to ensure there is no re- growth.
To conduct surveillance for GLR on two native grapevine species during the wet season (only present then) in Darwin and Palmerston.
Background:
GLR is caused by the fungus Phakopsora euvitis. It was detected in a suburb of Darwin on 17 July 2001. The National Grapevine Leaf Rust Eradication Program (NGLREP) commenced in March 2003. A quarantine area for GLR was gazetted on 14 April 2003. Phase 1, surveying all Darwin and Bakewell properties was completed on 30 June 2003. Phase 2, surveying Palmerston and part of the GDRA and commence grapevine removal was completed by December 2003. Phase 3, the surveillance of all remaining grapevines and two Ampelocissus spp. plants in the QA and selective surveillance in the NT was completed in June 2004. The program is now within the final Phase 4 that involves the ongoing surveillance of all remaining grapevines and two Ampelocissus spp. plants in the QA; other selective surveillance in the NT; implementation of a host-free period in Darwin and Palmerston in July/August 2005; the declaration of eradication of GLR from the NT by June 2006; and the implementation of stand down processes.
Results:
Phase 4 commenced with 39 007 properties surveyed and 256 grapevines on 193 properties. At 30 June 2005 there were only 210 grapevines on the remaining 164 properties.
The surveillance program has not identified any GLR in Palmerston since November 2003. The surveillance in Darwin continued to detect GLR until October 2004. Between November 2004 and March 2005 there were no detections in Darwin. However, in April 2005 three GLR positive grapevines were identified. One of the grapevines was previously unknown and was GLR-positive and was the infection source for the previously two negative grapevines. In addition, the first recorded natural GLR positive infection of a native grapevine in the field was identified. All plants were removed. Darwin has remained GLR-free since this incident.
The program has continued to monitor a selected number of grapevines in Katherine, Adelaide River, Batchelor, Corroboree and Pine Creek. Ongoing surveys for GLR in Borroloola, Groote Eylandt, Kununurra, Nhulunbuy, Bathurst Island and Melville Island are included in the NAQS annual surveys of these regions. All grapevines were negative for GLR.
A second independent review was conducted in October 2004 by two members of the original review team. They reviewed the implementation of the previous review and provided a further nine minor recommendations, which have all been actioned.
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The Scientific Advisory Panel revisited Darwin in December 2004. It reviewed the implementation of its previous recommendations, the science of the eradication program, and the research project on the pathology of GLR and immunity identification in the Australian grapevine germ plasm.
Media and consultation
A special “Thank you” advertisement was aired on local television, thanking the community for their cooperation in the survey part of the eradication campaign. The program has also been featured in national grape and wine industry magazines.
Commercial grape growers in Ti Tree have been briefed on the program’s progress. The website has received over 7000 hits and has provided the best platform to communicate to the grape and wine industries. A monthly newsletter is posted on that site. The newsletter is also circulated to a broad network from industry and government across Australia.
The National Vine Health Steering Committee, which is a national committee made up of State and Commonwealth agencies and grape and wine industry representatives has been briefed on the program’s progress. This is the peak government and industry committee on all matters relating to the health status of grapevines in Australia, including any potential threats from overseas.
NGLREP provided displays and public awareness material at the Darwin Show and the Garden Spectacular, as part of DBIRD sites.
Conclusion:
Phase 3 of the work plan was completed and Phase 4 was commencement during 2004-05. This is the critical lead up time to the required disease-free period, prior to declaring the region GLR-free by June 2006. This goal appears to be achievable.
PROJECT: Provision of a Government Certification System as an Alternative to Interstate Certification Assurance (ICA) for Market Access of NT Produce
Project Officers: J. Swan, P. Cawdrey, A. Mullins, J. Lindsay, S. Cross, C. Ellis, A. Jacks and S. Chester
Location: Darwin, Katherine and Alice Springs
Objectives:
To provide market access for NT produced plant material to other States of Australia.
To provide plant health certificates specifying that entry conditions to those States have been met.
Background:
NT produce including fresh fruit, vegetables, cut-flowers and nursery stock destined to States which have quarantine entry requirements, must be certified either by plant health certification or ICA. Most producers have opted for ICA accreditation, which allows self-certification. Where ICA arrangements are not available for a particular product, or consignments are irregular or few in number to make ICA economical, DBIRD may provide a plant health certificate based on inspection or other procedures.
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Nationally agreed ICA arrangements for cut-flowers and nursery stock have either not been developed, or are yet to be approved. NT growers in these industries therefore must submit to departmental inspection to obtain government certification before exporting to States which have entry restrictions.
Method:
The method for obtaining these services was described in the 2002-03 Technical Annual Report.
Results:
In 2004-05, staff made 811 visits for on-farm product certification or endorsement.
PROJECT: Market Access for NT Produce under Approved Interstate Certification Assurance (ICA) Arrangements
Project Officers: J. Swan, P. Cawdrey, A. Mullins, S. Cross, S. Chester, J. Lindsay, C. Ellis and A. Jacks
Location: Darwin, Katherine and Alice Springs
Objective:
To maintain market access within Australia for NT horticultural produce under approved ICA arrangements.
Background:
ICA is a system of plant health certification based on quality management principles. ICA provides an alternative to traditional plant health certification involving DBIRD inspectors. Traditionally, inspectors supervised treatment and/or inspected produce and issued plant health certificates for the movement of produce intrastate or interstate.
Under ICA, a business can be accredited to issue plant health assurance certificates for its produce. To be accredited, a business must be able to demonstrate it has effective in-house procedures in place that ensure produce consigned to intra and interstate markets meets specified quarantine requirements.
Method:
The method of providing these services was described in the 2002-03 Technical Annual Report.
Results:
Operational procedures have been developed for a range of treatment and condition requirements including:
• dipping; • flood spraying; • low volume non-re-circulating spraying; • fumigation; • heat treatment (vapour heat and hot water); • cold treatment; • hard green/mature green/unbroken skin condition; • pre-harvest treatment and inspection; • splitting and re-consigning certified produce.
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Over 800 arrangements are currently utilised by more than 450 businesses in the NT.
During the year, one ICA breach was detected in Alice Springs. A consignment of mangoes originating in Queensland and reconsigned from South Australia was found to be infested with live Queensland fruit fly larvae. The consignment was seized and destroyed and the breach was referred to Queensland authorities for follow-up.
Further operational procedures will be developed as required.
PROJECT: Dissemination of Plant Health Information
Project Officers: Plant Health Branch Personnel
Location: NT-Wide
Objective:
To provide relevant information and awareness to industry, DPIFM staff, other NT government departments, the Commonwealth and interstate primary industry and environmental agencies and the general public on plant health requirements and arrangements in the NT.
Background:
The Plant Health Branch is responsible for keeping industry, the public and government well informed of all matters relating to plant health. This includes production and protection issues such as pest and disease management, incursion management and quarantine movement requirements for plant material between regions of Australia.
Various arrangements have been developed under an interstate certification assurance (ICA) system approved nationally for market access of plant material. Advice regarding ICA and alternate Government certification methods is provided.
Method:
Various Plant Health Branch members represented the NT at teleconferences or meetings both locally and interstate. The interaction during these meetings ensures that current information is provided and received and that new strategies are developed to maintain plant health status in the NT and in other jurisdictions.
Members provided a range of briefings and advice on plant health matters to DPIFM executives, other NT government departments, and interstate and Commonwealth primary industry and environmental agencies.
Websites continued to be developed for the general public and industry to provide information on quarantine, ICA, plant health, NT insects, plant pests and diseases, exotic incursions and other relevant information.
Branch staff responded to email, telephone and direct enquiries from both industry and the general public on plant health matters.
Reference material and other documented information was produced and distributed to industry and other relevant stakeholders by post, electronic communication and, when required, and by personal visits.
Training packages were delivered to industry and staff through a range of mechanisms.
Staff routinely attended regional shows and provided media interviews to highlight current issues and disseminate timely information.
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Results:
During 2004-05 the NT Quarantine Section staff:
• Processed more than 1500 telephone enquiries from the general public and industry.
• Attended grower properties, nurseries, florists and fresh fruit and vegetable outlets on a routine basis to check compliance and advise on new conditions.
• Provided on-farm consultations for NT growers. During 2004-05, over 1100 consultations were conducted with more than 500 businesses in the NT. Details are maintained on the Plant Health Information System database.
• Continued to develop the NT Quarantine website to enable the public ready access to information on current plant and plant product movement conditions and other issues of quarantine interest.
• Provided an in-office service to growers and the general public.
The Plant Pathology Section staff:
• Processed more than 1720 disease enquiries (including grapevine leaf rust samples) from the general public and industry at the Berrimah laboratory and 97 in Katherine.
• Added 59 new accessions to the disease collection, bringing the total accessions to 3604.
• Provided an in-office and on-farm visit service to growers and the general public.
The Entomology Section staff:
• Processed more than 1051enquiries from the general public and industry.
• Added 912 specimens to the database, bringing the total to 40 415.
• Attended 324 grower properties for research or extension matters.
• Provided an in office service to growers and the general public.
• Developed a website for easy access to information on endemic and exotic pests and their control, with 104 fact sheets. There were 3597 visits to the website by 1856 separate visitors.
The Management staff:
• Maintained NT representation on a range of plant health technical meetings (>70), mostly by participating in teleconferences.
• Participated in nine workshops and other focussed meetings to present relevant information.
• Attended a range of plant biosecurity meetings, including six national and 21 at the Territory level.
• Attended 13 professional meetings, delivered three presentations to technical groups.
• Delivered four media interviews or provided articles for dissemination of information.
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PROJECT: Inspection of Shipping Containers from Giant African Snail (GAS) Infested Countries under NT Legislation
Project Officers: J. Swan, P. Cawdrey, A. Mullins, J. Lindsay, S. Cross and B. Dilley
Location: Darwin
Objective:
To provide prompt and efficient quarantine clearance and/or subsequent treatment of goods originating from GAS infested countries identified under NT legislation.
Background:
GAS is considered by most authorities to be the world’s most damaging land snail. It is known to attack over 500 plant species including legumes, cucurbits and many other vegetables as well as a wide range of tropical ornamentals. GAS has long been a concern to the NT due to its presence in all countries in SE Asia and the ease of its transfer or of its eggs by shipping containers.
GAS is identified on the NT notifiable pest list and additional legislation has been enacted under the NT Plant Disease Control Act to minimise the risk of its entry to the Territory. This includes a more extensive list of countries from which cargo should be inspected because GAS is endemic in them.
Method and Results:
The method for providing these services has changed since the responsibility to provide barrier quarantine services was transferred from the NT to the Commonwealth in December 2003. AQIS has reviewed the NT and AQIS GAS target country lists to more accurately reflect published scientific data on the distribution of the pest and to harmonise these list for use across Australia.
In November 2004, AQIS produced a draft list of GAS target countries and the NT removed four countries from their list by gazettal notice the following month. In May 2005, the Commonwealth produced a draft list which increased the target countries from 17 to 56 and the Territory deleted a further four countries from its list by amending the gazettal notice. AQIS considers that the revised draft list which has now been placed on the World Trade Organisation Website for international comment could be implemented nationally within 2005. AQIS is maintaining the current NT GAS country list and requirements whilst the review is being finalised.
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PROJECT: Surveillance of Imported Plant Material for Pests and Diseases
Project Officers: J. Swan, I. Haselgrove, P. Cawdrey, S. Cross, B. Dilley, A. Mullins, J. Lindsay, C. Ellis and A. Jacks
Location: NT-Wide
Objective:
To ensure that any plant material entering the NT from other regions of Australia complies with movement conditions under NT legislation.
Background:
The local horticultural industries are advantaged by reduced production costs and better market opportunity when the NT is free from pests and diseases that occur in other regions of Australia.
Plant material (fresh fruit and vegetables, cut-flowers and nursery stock) entering the NT must comply with legislation and have accompanying certification to confirm that these requirements are met.
The NT accepts plant health certificates and interstate certification assurance (ICA) certificates.
Method:
An ongoing inspection program is maintained at NT florists, nurseries, and fresh fruit and vegetable importers to inspect produce from risk areas of Australia.
Targeted pests include western flower thrips, spiralling white flies, Mediterranean fruit flies, banana flies, cucumber flies and red imported fire ants (RIFA).
The NT targets RIFA as a particularly serious environmental and agricultural pest and high-risk materials which may harbour this pest are routinely inspected on arrival by the RIFA surveillance officer.
Results:
The NT has maintained freedom from these targeted pests
Significant detections
A consignment of 175 citrus plants ex Queensland was returned to Rockhampton, Queensland due to incorrect certification.
Numerous consignments of papaya from Queensland were destroyed due to the detection of the notifiable disease, papaya black spot.
A consignment of 4000 grapevine plants was returned to WA due to incorrect certification.
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PROJECT: Surveillance for Exotic Fruit Flies
Project Officers: I. Haselgrove, B. Dilley, J. Starr and D. Salter
Location: Territory-Wide
Objective:
To make early and timely detection and identification of exotic and interstate fruit flies which are not endemic in the NT.
Background:
Monitoring for pest species of fruit flies occurring interstate and overseas but not in the NT is carried out on a fortnightly basis during the dry season or more frequently if conditions require it.
Strategic monitoring grids are located throughout the main urban areas and across the great majority of horticultural production areas of the NT.
Early detection of pest species is extremely beneficial both for feasibility and cost reduction.
Method:
Lures are assembled in Darwin and dispatched to the regions monthly. Since December 2003, AQIS personnel have serviced Nhulunbuy with materials supplied by DPIFM.
All specimens (except those from Alice Springs and Ti Tree) collected from traps are sent fortnightly to the Darwin office for identification. Procedures are in place to enable Alice Springs to identify catches in Central Australia.
Results:
A single Bactrocera neohumeralis specimen of the lesser Queensland fruit fly was detected in Nhulunbuy. This fly is endemic in Queensland and northern New South Wales.
No exotic flies were trapped during the period covered by this report.
PROJECT: Surveillance for Red Imported Fire Ants
Project Officers: B. Dilley, C. Ellis, A. Jacks, J. Swan and G. R. Brown
Location: NT-Wide
Objective:
To detect as early as possible any red imported fire ant (RIFA) incursion in the NT by passive and active surveillance methods.
Background:
RIFA, Solenopis invicta is an exotic ant species first detected in Queensland in early 2001. An eradication program for this pest is currently under way throughout the greater Brisbane area. RIFA is a serious agricultural and social pest that can affect our lifestyle. It can adversely affect our agricultural, horticultural
199 Resource Protection and tourism industries, and may become a severe nuisance to the general public. Native flora and fauna, infrastructure, equipment and machinery could also be affected.
Early detection is extremely important, since it will reduce the cost associated with potential eradication.
All areas of the NT are at risk of an invasion by RIFA. However, the three major urban centres of Darwin, Katherine and Alice Springs are at a high risk. Monitoring is therefore concentrated in those areas.
Method:
Surveillance is conducted through a range of strategies that were described in the 2002-03 Technical Annual Report. High-risk sites are checked on a monthly basis.
Results:
Visits were conducted to new risk sites during the year after receiving reports from members of the public and from high-risk industries. The sites were physically checked for RIFA, logged by GPS and ant samples were taken for identification. No RIFA were found.
Although this ant is very similar to the local ginger ant, few enquiries concerning this pest were received. No RIFA were detected in the NT during the year.
RIFA surveillance will continue in the coming year at a reduced rate as the risk of an incursion from Queensland diminishes.
PROJECT: Post-Barrier East Timor Surveys for Exotic Plant Pests and Diseases
Project Officers: E. Crowson, G. R. Brown and E. S. C. Smith
Location: Darwin and Katherine Regions
Objective:
To conduct six-monthly surveys to detect incursions by exotic plant pests, diseases or weeds and exotic bees or their parasites in the main military and refugee activity areas during the East Timor disturbance of late 1999.
Background:
In the wake of the East Timor political disturbances in 1999, two initial surveys (NT surveys 1 and 2) were conducted by DPIFM. These were performed in October-November 1999 and May-June 2000 and were reported in the 1999-00 Technical Annual Report. A subsequent survey (NT survey 3) was conducted in May-June 2001 and was reported in the 2000-01 Technical Annual Report and NT survey 4 was conducted in December 2001-February 2002.
Following consultations with the Commonwealth Department of Agriculture Forestry and Fisheries, an agreement for regular surveys to be performed as part of an Australia-wide post-barrier exercise was reached. A consultancy agreement entitled “East Timor – Post Barrier Surveys in the Northern Territory” was concluded with the Commonwealth Government in April 2003 which required the NT to conduct two surveys per year, one during the wet season and the other during the dry season until the end of 2004.
Surveys conducted from 12 August to 21 November 2003 (NT survey 7) and from 26 April 2004 to 27 August 2004 (NT survey 8 were reported in the 2003-04 Technical Annual Report. This is a report on the final NT 200 Technical Annual Report 2004-05 survey 9 (from 30 September to 22 December 2004) and concludes the agreement with the Commonwealth for this surveillance activity.
Results:
During NT survey 9, only three samples were collected and submitted for identification. The reduced number of samples collected in comparison to previous years (e.g. 440 samples during 2002; 68 during 2003) was a result of the reduced collection and identification of arthropod, disease and weed species previously taken during the preceding seven surveys conducted across those same areas. Where the identity of organisms observed in the field was known or recognised as previously having been taken, samples were not re- collected.
Specimens collected during earlier surveys that have now been identified were presented, with their relevant collection data, in previous reports. No further identifications are reported here. However, a series of psychid larvae collected from Poinciana in 2003 have yet to be determined. This could take many years. No further samples that have yet to be identified were collected during the 2004 surveys
Some sites which had been previously examined during Post-East Timor surveys could not be visited within this period due to heightened security alerts. Thus, access to the RAAF bases in Darwin and at Tindal, near Katherine was denied. Due to large urban development projects, areas of land in the Darwin Wharf precinct, East Arm Wharf, the Trade Development Zone, Darwin Business Park, Robertson Barracks, Wishart Road, Mount Bundy Training Area and Kangaroo Flats Training Ground have been cleared of vegetation and various earthworks constructed. This activity has greatly lessened the risk of targeted species (and particularly weeds) surviving in these areas.
No new or targeted insects or fungal diseases of economic importance were identified during NT survey 9. However, the giant sensitive weed, Mimosa pigra was detected again on the RAAF golf course and at Winnellie. This weed was reported in previous surveys and is under an active eradication program. In addition, Mimosa pudica was detected on Gardens Park golf course. This is a rarely reported native species.
The introduced species Eulopia graminia (a ground orchid) was not seen during the latest survey although it had been previously detected at two sites on the Darwin golf course. This is an introduced species with a potential to become a problem weed. Similarly, there were no new detections of the fringed spider flower (Cleome rutidosperma) infestations previously reported.
Katherine roadside verges were regularly travelled by specialist quarantine and plant health personnel who continue to look for any suspect plants, bees or symptoms of plant damage.
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PROJECT: Management and Responses to Incursions of New Pests and Diseases
Project Officers: All Branch Officers
Location: NT-Wide
Objective:
To provide a timely response to incursions or potential incursions of new exotic plant pests, diseases and weeds to increase the feasibility of eradication and minimise its cost.
Background:
The NT is potentially subject to entry by both interstate and international exotic pests and diseases that can affect the horticultural and agricultural industries and the community. Experience has shown that early detection and rapid response can increase the feasibility of eradication and greatly reduce costs. The Department has primary responsibility for the surveillance, detection, identification and, (at least) the initial response to any incursion of a previously unreported plant pest or disease and weed.
Method:
Detection of an organism considered not present in the NT requires a situation report, which then requires the involvement of a specialist to identify a potentially new pest or disease. The report must be confirmed and notification must be given to appropriate senior staff, legal officers, Ministerial staff, specialist interstate plant pest/disease committees and Commonwealth and State authorities.
Management team structures and tasks have been established and any incident is managed according to the Departmental Response Plan. In future, incursion responses will follow the nationally accepted PlantPlan.
Results:
The national 1800 hotline (EPPH) is operating through a call centre and relevant calls are forwarded to the NT for further response. During the year, some 22 such calls were recorded and finalised.
The Branch was involved in several incidents relating to exotic pest and disease incursions during the year:
Two new suspect detections occurred in the NT in early September. Suspect exotic organisms, black Sigatoka (later determined as Periconiella speckle) and fruit fly were identified as endemic species. Bactrocera melanothoracica had not been known outside Torres Strait and Cape York. Further samples and surveillance were undertaken against these two suspect species but there were no additional suspect detections.
The golden mystery snail Pila (Pomaceae) bridgesii (Ampullariidae), an exotic species but apparently naturalised in a Queensland river was detected in an aquarium by the quarantine officer in Katherine. It has the propensity to become an environmental and economic pest in the NT and poses a danger to wetland environments and possibly to human health. It could be moved through the aquarium trade by which it had previously been detected in a dam on an out-station near Broome in Western Australia. Further detections were made in Darwin aquariums and the situation is now being managed by the aquatic pest group in the Fisheries Group of the Department.
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Orange rust of sugarcane (Puccinia kuehnii) was found on the sugarcane relative Saccharum spontaneum at the Daly River by North Australian Quarantine Strategy scientists. This was a new NT record for this disease.
Following a detection of European house borer in pine plantations in Western Australia, staff visited all timber importers and traders in the NT. Members of the local Australian Environmental Pest Managers Association (AEPMA) were also contacted with information on the outbreak and a meeting attended to present the latest details of the WA incursion.
As part of the national surveillance strategy following the detection of citrus canker in Queensland, three citrus blocks of over 600 trees each have been surveyed in the NT. No suspicious symptoms of canker were detected.
The NT Quarantine Section has the responsibility to detect pest species endemic in other Australian jurisdictions but not present in the NT, but which may enter on traded plant products. Similarly, some NT plant products are inspected and certified as free of pests and diseases before being transported interstate. Some market access issues that arose during the year included:
Cercospera myrticola leaf spotting was noticed on a few plants of Syzygium forte nursery stock in a consignment to Western Australia. Although identified as a probable native species, it had not previously been recorded in the NT and the plants were removed from the shipment.
Interstate shipments of grapevines, citrus plants and papaya fruit were detected after entry to the NT without appropriate certification and returned to the state of origin or destroyed. Similarly, a consignment of mangoes at Alice Springs was detected with fruit fly infestation. The shipment had entered via South Australia with ICA certification, but originated in Queensland. Queensland authorities were notified and have investigated the ICA breach.
A new detection of the dry wood termite Cryptotermes dudleyi (Banks) (Isoptera: Kalotermitidae) was found at a Nightcliff house previously known to be infested. This species has established in North Queensland but was (hopefully) eliminated from the NT by removal of infested timber. A briefing on this situation was presented to a meeting of AEPMA representatives.
As reported in the 2003-04 Technical Annual Report, the swollen helicella snail Cochlichella barbara (Linnaeus) (Eupulmonata: Helicidae) was detected on one property near Alice Springs. Control measures have been applied and this pest, widespread in southern areas of Australia, appears to be restricted to the single property in the NT.
The currant-lettuce aphid Nasonovia ribis-nigri, a major pest of lettuce in Europe and NZ is considered to have arrived in Tasmania in January 2004 and Victoria in April 2005. The NT will not impose movement conditions for susceptible produce, but surveillance on two properties producing lettuce in Alice Springs has been conducted at three monthly intervals but no aphids have been detected.
Surveillance programs that target fruit flies exotic to the NT and the red imported fire ant were continued throughout the year and are reported elsewhere. Similarly, the National Grapevine Leaf Rust Eradication Program is reported separately. The ninth and final Post Barrier East Timor survey in the NT was also conducted during this period. Results are presented in a separate report.
A potential weed, Neptunia plena is prohibited entry to Australia but was recorded growing in a waterhole on a property at Virginia. It was controlled in October 2004, with follow-up into 2005, using the herbicide fluroxypyr and hand removal. By mid June 2005, there had been no regrowth, but monitoring of the area must continue for five to 10 years to check for regrowth and to carry out follow-up control if necessary.
Lasiacis ruscifolia (climbing tribisee) a bamboo-like potential weed species was found at four suburban sites in Darwin.
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PROJECT: Plant Health Reporting Requirements
Project Officers: I. Kilduff, E.S.C. Smith, I. Miller, J. Alcock and V. Kawaljenko
Location: Darwin
Objectives:
To provide timely and appropriate reports on plant health policy and operations.
Background:
The Plant Health Branch has the prime responsibility for plant quarantine within the NT and to maintain interstate trade in plant products. To operate effectively, these functions require an appropriate framework for operational procedures and a reporting system to meet the Territory’s jurisdictional, national and international obligations.
Method:
Various members of the Branch are delegates on national committees to provide consultation and reporting functions necessary for the effective operation of national and State/Territory plant health responsibilities.
Results:
During the year, the Branch maintained representation on, and reported to, the following technical committees:
• Plant Health Australia; • the Executive Committee for the Cooperative Research Centre for Tropical Plant Protection; • the Product Integrity and Security Committee; • the Signatories Working Group; • the Plant Health Committee; • the Domestic Quarantine Market Access Working Group; • the Registration Liaison Committee; • the Consultative Committee on Exotic Plant Pests; • the Consultative Committee on Exotic Plant Incursions; • NT Weed Risk Assessment Technical Group: • the North Australian Quarantine Strategy Stakeholders’ Committee; • the North Australian Quarantine Strategy Technical Advisory Panel; • the North Australian Quarantine Strategy Joint Operational Group; • the Black Sigatoka Technical Working Group; • the National Diagnostics Network Steering Committee; • the National Vegetable Pathology Working Group; • the Torres Straits Fruit Fly Technical Advisory Panel; • the Scientific Advisory Panel for the National Grapevine Leaf Rust Eradication Program; • the National Monitoring Group for the Imported Fire Ant Eradication Program; and • the Mangoes to China Market Access Steering Committee.
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Appropriate NT responses were carried out for surveillance and eradication programs within the NT (as reported elsewhere in this Technical Annual Report) and for pest incursions in other States. The latter included participation in the decision-making processes, generally via teleconferences, of the Red Imported Fire Ant Eradication Program, the National Citrus Canker Eradication Program and incursions of the currant- lettuce aphid Nasonovia ribis-nigri, European house borer, Japanese pine sawyer beetle, willow sawfly, scotch broom, and white rust of rocket.
PROJECT: Plant Health Legislation
Project Officers: I. Kilduff, I. Miller and E. S. C. Smith
Location: Darwin
Objective:
To facilitate appropriate legislation to enable the NT to trade in plant products and maintain its relative freedom from incursions of plant pests and diseases.
Background:
The existing Plant Diseases Control Act 1979 has deficiencies that were identified in an NT Quarantine Review in 1999. Occurrences of the exotic fruit fly and Panama disease have also tested the usefulness of the Act, while control of diseases such as grapevine leaf rust require legislative provisions that enable effective survey and eradication activities. However, the current Act continues until a new Act is promulgated.
Method:
The process to seek approval to draft new plant health legislation for the NT began in November 2002 and was based on a recommendation in the NT Quarantine Review on quarantine procedures in the NT during 1999. Parties interested in the Territory's plant-based industries and related industries were consulted as part of the initial process.
In June 2003, the NT Government approved drafting of a new Plant Health Bill and the release of a public discussion paper. The discussion paper was widely distributed and outlined the necessity to create awareness for new plant health legislation and the type of changes being proposed. The paper invited public comment to assist in the preparation of drafting instructions. The discussion paper was explained at a series of public meetings during the latter half of 2003.
As a result of public consultation, an examination of interstate legislation and consideration of the existing NT legislation, the drafting instructions for the proposed Plant Health Bill were forwarded to Parliamentary Counsel in June 2004.
Further public consultation will take place after the initial drafting and before recommending that the Bill be introduced in the Legislative Assembly.
Results:
A Plant Health Bill was drafted in 2005. Drafting instructions for Plant Health Regulations, which will assist in giving effect to the Act, are also being developed. Approval will be sought to release both the draft Bill and the draft Regulations for public consultation before recommending that the Bill be introduced in the Legislative Assembly.
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Management staff developed policy and liaised with other relevant personnel in the development of this legislation.
Seventeen gazettal notices were published under the Plant Diseases Control Act during the reporting period. Four were in relation to a citrus canker outbreak within Australia, 10 were quarantine notices for Panama disease on properties growing or that had grown bananas and two to change the Territory’s target country list for the giant African snail.
PROJECT: Targeted Horticultural Surveillance in the Darwin Rural Area
Project Officer: B. Gower
Location: Darwin Region
Objective:
To conduct surveys to detect incursions of exotic plant pests, diseases or weeds as an adjunct to the Post – Barriers East Timor Surveys.
Background:
As a result of the East Timor political disturbance in 1999 six surveys were conducted in the main area of military and refugee activity. These surveys were at the request of Biosecurity Australia and performed as part of an Australia-wide post barrier exercise.
As an adjunct to the Post East Timor Surveys targeted horticultural surveillance has been conducted in the Darwin rural area for detection of exotic plant pests and diseases. A total of 913 blocks have been surveyed.
Results:
Targeted areas Blocks surveyed Surveyed (%) * Marrakai 241 99.59 Darwin River 376 94.15 Buckley Road 24 95.84 Lambells Lagoon 56 92.86 Wanderrie North 216 89.82
* Properties not surveyed could not be accessed due to locked gates.
The survey indicated: 198 properties (21.68%) had banana plants 283 properties (30.99%) had mango trees 208 properties (22.78%) had citrus trees 199 properties (21.79%) grew Asian vegetables 3 properties ( 0.32%) had grapevines
Referrals
Seventeen specimens or enquiries were referred to Plant Pathology Three specimens were referred to the red imported fire ant surveillance officer Five specimens were forwarded to NT Health Five specimens were referred to Entomology No new or targeted insects or fungal diseases of economic importance were identified.
206 Technical Annual Report 2004-05
PROJECT: Control of Use of Agricultural and Veterinary Chemicals
Project Officers: I. Kilduff and J. Alcock
Location: Darwin
Objective:
To develop new legislation to control the use of agricultural and veterinary chemicals, fertilisers and sock feeds.
Background:
The new Agricultural and Veterinary (Control of Use) Act was assented in June 2004.
Cabinet provided $100 000 for the administration of the Act including the appointment of a new position of Chemical Adviser.
Results:
The Chemical Adviser, who was appointed in December 2004, has contributed to the development of necessary methods and procedures for the administration of the legislation. The Minister appointed John Alcock, who had been responsible for the development of the legislation, as Chemicals Coordinator.
The Act was commenced on 16 May 2005 and the Regulations on 31 May 2005. DPIFM now licenses horticultural spray applicators, pilots and businesses. It also investigates spray drift problems. The Chemical Adviser has responded to eight persons that were concerned about the use of pesticides.
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HORTICULTURE SERVICE: HORTICULTURE INDUSTRY INFORMATION SERVICE
Program: Horticulture Industry Development Service
PROJECT: Sector Liaison
Project Officer: M. Connelly
Location: NT-Wide
Objective:
To ensure that the targeted needs of the horticulture industry are being effectively met through enhanced communication between the government and industry
Background:
The mission of the Sector Liaison staff is to provide connectivity between industry stakeholders and government departments. This is achieved mainly by facilitating industry development plans for the different grower groups. Based on such plans, targeted research and extension activities can be initiated. This year 40 activities were conducted covering a wide range of subjects, which attracted 694 participants. Among the main successful avenues for transfer of technology are the annual shows in Alice Springs, Katherine, Darwin and Fred’s Pass, in addition to the Katherine Research Station’s Farm and Garden Day, and the NT Tropical Garden Spectacular. All these events targeted the specific needs of primary producers and the general public (see Table 1).
Results:
The nursery industry
A skills audit indicated a need for more education on plant health issues, environmental matters and government regulations such as the Weeds Act, spray-drift and water run-off.
The Horticulture Division hosted the first Nursery Trade Day in the grounds of Berrimah Farm. Attendance was small but the interaction between the different sectors of the ornamental industry was positive and many new alliances were formed.
The cut-flower industry
In early 2005, the NT cut-flower group (NTCFG) in cooperation with DPIFM established a company to commercialise four new varieties of ‘Darzing’ which were bred and registered by departmental horticulturists. In addition, DPIFM supplied the company with a number of the most promising non-‘Darzing’ varieties and inter-specific Zingiber hybrids.
NTCFG established an industry website, which is a key outcome of its 2005 industry development plan. The website is designed to display a range of tropical cut-flowers and foliage grown by the industry in the Top
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End. It also provides information on the availability of products needed by the industry and on how to use them.
The citrus industry
NT citrus growers have invested in a mandarin varietal rootstock trial to investigate the possibility of producing an out-of-season easy-peel mandarin. The trial started a year ago and will continue for about five years before selection commences.
The citrus plantings survey
This project has been completed. GIS technology was used for the spatial collection, storage and manipulation of citrus planning data. The final survey results are shown in Table 1.
Table 1. Details of citrus plants
Number of Number of Number of Number of Number of growers lemon trees grapefruit trees lime trees mandarin trees Darwin 20 4149 9143 9197 0 Katherine 8 26 982 20 909 728 372 Total 28 31 131 30 052 9925 372
The vegetable industry
Some concern has been expressed over the termination of the position of Communications Officer a year ago. Effective liaison with this group has faulted and although Horticulture has used the services of the Department of the Chief Minister and Ethnic Affairs for the translation of many publications, there is a need for a regular interpreter to maintain close relations with this group on all aspects of farming and environmental issues.
The Katherine horticulture advisory forum (KHAF)
A review was conducted in February 2005 of the strategic plan document “Future Directions for Katherine Horticulture”. The Horticulture Division and industry have been working together towards meeting the defined goals in the plan, under the guidance of KHAF. This includes such activities as liaising with the Katherine local best practice group, and defining biosecurity risks to the region.
The mango industry
The NT Mango Industry Association’s (NTMIA) Strategic Plan for 2003–06 is recognised as the industry development plan (IDP) for the mango sector. The plan has identified a number of projects to fulfil key strategies. The industry has shown strong commitment to the plan, working in close liaison with the department. There have been no changes to the projects listed in the plan since its inception.
Throughout 2004-05 the NTMIA board developed closer ties with NTHA in order to improve its service to members. NTHA provides all of the administration and communication support for NTMIA business. Hence liaison between NTMIA and the department operates through NTHA. The department monitors industry development on a regular basis through day-to-day communication with industry members, NTMIA board meetings, industry newsletters and through attendance at local industry meetings such as the pre-and-post mango season planning meetings. The Australian Mango Industry Association developments are monitored closely through direct contact with its industry development manager and newsletters.
Departmental officers attended and/or organised a number of development activities for industry in 2004-05 (see Table 2). These activities cover national, regional and local issues.
209 Horticulture
The horticulture partnership group (HPG)
HPG held its inaugural meeting on 9 June 2004. During 2004-05 the group met four times on 23 August 2004, 21 February, 7 March and 16 May 2005. Three vacant positions were filled during the year including the business and marketing positions.
Planning workshops were held during the year at which the group identified priorities for sustainable and profitable industry growth in order to achieve its vision of doubling the value of the Territory’s horticulture industry in five years.
Considerable time was also dedicated to consider mechanisms that will enable the NT horticulture industry to work cooperatively on packaging, marketing and supply. A pre-feasibility assessment was completed to analyse various horticultural marketing and organisational models and practices from around Australia to determine their suitability for improving marketing of NT produce.
The rambutan industry
The Australian Lychee Growers Association held its 6th national conference incorporating the first Australian Sapindaceae crop conference in Cairns on 15–17 September 2004. It was attended by the rambutan sector liaison officer and growers from the NT. A wide range of presentations were made by growers, industry bodies, researchers and international guests from Thailand, Taiwan and Hawaii. A poster was presented on the recent work carried out on the effects of rootstocks on rambutan tree size and yield in the NT.
In November 2004, Dr Sirichai Kanlayanarat from the Centre for Post Harvest Technology at King Mongkut’s University in Bangkok, Thailand visited rambutan growers. He met with growers and visited several packing sheds to look at post-harvest handling systems.
A rambutan growers’ meeting was held on 3 February 2005, where such issues as the importation of new varieties from overseas were discussed. Problems of plant management and specific requirements for post- entry quarantine were highlighted. The IDP was discussed and finalised for this year. The season’s round-up was generally good, except for some issues with the packaging supplier.
The melon industry
A survey was conducted on the needs of NT melon growers, to enable the Horticulture Division to efficiently serve this group. A strategy was developed to study the impact of the decline in the production of cucurbits. However, the problem did not occur in melon crops in that growing season. Work to utilise a SPAD meter to measure chlorophyll levels was initiated.
210 Technical Annual Report 2004-05
Table 2. Workshops/field days/shows/displays conducted by DPIFM Horticulture in 2004-05
Event Venue Date Presented by No Participants 1. Citrus “Making lime production profitable” NTHA 21/03/05 Geoff Walduck/Megan Connelly 8 2. Citrus “Fertigation workshop” Stan Robert’s property 14/06/05 Megan Connelly/Greg Owens/Steve Falivene 18 Humpty Doo 3. Citrus “Fertigation workshop” KRS 15/06/05 Megan Connelly/Greg Owens/Steve Falivene 9 4. Citrus “Growing strategies for 2005” Venn, Katherine 29/03/05 Mark Hoult/Megan Connelly 6 5. Citrus “Orchard happenings workshop” Katherine Training 31/07/04 Megan Connelly/Dr Andrew Krajewski/Dr 15 Centre/Venn Sonya Broughton 6. Cittgroup “Season round-up, where to from here” Venn, Katherine 25/02/05 Megan Connelly 8 7. Cittgroup “Season round-up, where to from here “ NTHA 17/02/05 Megan Connelly 9 8. Cut-flower “BEC/Frmbis presentation” NTHA office 09/11/04 Megan Connelly/Rod Murray/David Collison 15 9. Cut-flower “Curcuma hybrid block field walk” Horticulture block Berrimah 12/04/05 Doris Marcsik/Mark Hoult 7 10. Cut-flower “Cost of production workshop” NTHA office 28/05/05 Megan Connelly/Peter Shepherd 8 11. Cut-flower “Cost of production workshop” NTHA office 18/06/05 Megan Connelly/Peter Shepherd 8 12. Cut-flower “Alpinia borer update meeting” NTHA 21/06/05 Megan Connelly/Entomology Staff 15 13. Food processing forum TDZ 03/06/05 Chris Wicks 33 14. LBPG “Irrigation monitoring” Venn- Planet Mango 17/08/04 Chris Wicks/grower discussion 20 15. LBPG “Irrigation monitoring” Ballongilly Farm- Katherine 19/08/04 Chris Wicks/grower discussion 8 16. LBPG “Irrigation monitoring” Mataranka 31/08/04 Chris Wicks/grower discussion 12 17. Mango “Canopy management options workshop” Growers Orchards 19/03/05 Greg Owens 35 18. Mango “Effective spray application workshop” Growers orchards 12/02/05 Greg Owens 30 19. Mango “Managing in the mango industry” KRS 08/09/04 Geoff Walduck/David Hamilton 11 20. Mango “Managing in the mango industry” BARC 10/09/04 Geoff Walduck/David Hamilton 7 21. Mango “Nutrition management” Berry Springs 07/05/05 David Hamilton/Megan Connelly 25 22. Mango “Pest and disease management in WePac Berry Springs 11/06/05 David Hamilton/Barry Conde/Deanna Chin 24 mangoes” 23. Mango “Post-season meeting” KRS 10/02/05 Greg Owens/David Hamilton 30 24. Mango “Post-season meeting” Berry Springs 05/02/05 Greg Owens/David Hamilton 75 25. Mango “Supply chain review and development Howard Springs 20/4/05 Greg Owens/David Hamilton 40 forum” 26. Mango “Pre-season meeting” KRS 21/9/04 David Hamilton 25 27. Mango “Pre-season meeting” Berry Springs 25/9/04 David Hamilton/Greg Owens 40 28. Mango “Sea-freight meeting” KRS 2/9/04 Peter Johnson WA Ag/Jill Parker 7 29. Mango “Sea-freight meeting” KRS 7/10/04 Peter Johnson WA Ag/Jill Parker 8 30. Mango “R&D review” Katherine & Kununurra 14/3/05 David Hamilton/Julie Bird/Bob Williams QDPIF 7 31. Mango “R&D review” Darwin 17/3/05 David Hamilton/Bob Williams QDPIF 5 32. Nursery “Frangipani field walk” Horticulture block 24/9/04 Doris Marcsik/Mark Hoult 15 211 Horticulture
33. Nursery “IPM workshop” Howard Hall 15/10/04 John McDonald/Megan Connelly 22 34. Nursery “Skills audit presentation” NTHA office 6/12/04 Megan Connelly 17 35. Nursery “Trade day” Berrimah Farm 19/4/05 Megan Connelly/Annie Black 25 36. Nursery “Production and marketing workshop” NTHA office 21/2/05 Megan Connelly/Peter Shepherd 6 37. Nursery “Production and marketing workshop” NTHA office 4/4/05 Megan Connelly/Peter Shepherd 6 38. Nursery “IPM workshop” NTHA office 13/5/05 Megan Connelly/John MacDonald 21 39. Show - Katherine Katherine Showground 15-17/7/04 Katherine Horticulture team - 40. Show - Alice Springs Show grounds 2-3/7/04 Horticulture team - 41. Show – Darwin Show grounds 22-23/7/04 Horticulture team - 42. Show - Fred’s Pass Show grounds 21-22/5/05 Horticulture team - 43. Show - KRS Farm & Garden Day KRS 17/3/05 Horticulture team - 44. Show - Tropical Garden Spectacular George Brown Botanic 9/8/04 Horticulture team - Gardens 45. Table grape “Managing nematodes workshop” AZRI 6/4/04 Andrew Nesbitt/SARDI/Bayer 5 46. Vegetable “Hydroponic and shade house NTHA office 12/10/04 Greg Owens/Jeremy Badgery-Parker NSW Ag 9 production workshop” Total 694
212 Technical Annual Report 2004-05
PROJECT: Cittgroup Activities for 2004-05
Project Officer: M. Connelly
Location: NT-Wide
Objective:
To provide Northern Territory citrus growers with relevant workshops, seminars and field days to improve their knowledge.
Background:
The role of the Cittgroup Coordinator is to organise technical workshops/field days in the Katherine and Darwin Regions and to include Kununurra when possible.
Activities
• Citrus leaf miner discussion group, Katherine 01/07/04 • Mandarin planting day, Darwin 31/06/04 • “Orchard happenings” workshop Katherine 31/07/04, Kununurra 01/08/04 • Seasonal roundup meeting, Darwin 17/02/05, Katherine 28/02/05 • Production costs and profitability for lime producers, Darwin 21/03/05 • Fertigation systems and effective delivery workshop, Darwin – 14/06/05, Katherine – 15/06/05 and Kununurra – 17/06/05.
Outcomes
An initiative of the NT citrus growers has been to commit funds and land to a mandarin varietal rootstock trial to investigate the possibility of producing an out-of-season easy-peel mandarin.
Growers are starting to appreciate the important connection between basic tree phenology, yield and profitability.
Katherine citrus growers produced a best practice paper on the control of the citrus leaf miner.
Figure 1. NT citrus growers establishing the mandarin varietal rootstock trial – June 2004
213 Horticulture
PROJECT: Mango Supply Chain Code of Practice
Project Officers: D. Hamilton and NTMIA Board members
Location: Berrimah Farm
Objectives:
To assist the NT Mango Industry Association (NTMIA) to develop a mango industry code of practice document that addresses commercial relationships between supply chain members and best practice product handling.
To provide assistance to relevant peak bodies to promote the code nationally.
Background:
In May 2003, the Australian Mango Industry Association (AMIA) released a consultative draft document of a mango industry voluntary code of practice for public comment. Subsequently all sections of the code were revised and there was agreement in principle on all sections except wholesaler.
In September 2003, a committee was formed to develop a legal definition of wholesaler terms of trade, consisting of AMIA and Horticulture Australia Limited (HAL) with the Australian Chamber of Fruit and Vegetable Industries representing wholesalers.
In February 2004, AMIA became the administrator of the project. Later in 2004 the review of the Retail Grocery Code of Conduct commenced. The outcomes of the review are expected to shape the mango code, particularly in the context of the wholesalers’ terms of trade.
Results:
The committee was not able to reach agreement on a legal definition of wholesaler terms of trade.
A final mango code document was developed and was accepted by all chain partners except the wholesalers.
The final report to HAL on the code process was completed.
This project was funded by HAL.
214 Technical Annual Report 2004-05
PROJECT: Mango Harvest Labour Strategy
Project Officers: D. Hamilton and NTHA Staff
Location: Berrimah Farm and the NTHA Office
Objective:
To facilitate the development of self-directed industry/stakeholder groups to address mango harvest labour issues.
Background:
The project commenced in November 2002 with a forum between industry members and stakeholders. This was an NTMIA initiative to identify issues impacting on harvest labour shortages. Subsequently the forum formed a group know as the mango harvest labour strategy group (MHLSG).
In July 2003 MHLSG developed strategies with action plans for the 2003 season. However, the 2003 season was small compared with the 2002 season, so there was not possible to test the strategy.
In April 2004, MHLSG recognised the need for a committee to coordinate strategy implementation. The committee consisted of key harvest labour providers, NTHA and NT Government representatives.
Results:
Close links were established with stakeholders in order to maintain productive relationships.
Record numbers of workers were recruited during the 2004 season. As a result a 34% increase in the volume of fruit was achieved compared with the previous record in 2002.
A final report was presented to the NTMIA board in May 2005.
A presentation was made to industry at the NTMIA pre-season meeting in August 2005.
PROJECT: The NTMIA Communications Project
Project Officers: D. Hamilton and NTMIA Board Members
Location: Berrimah Farm and the NTHA Office
Objective:
To assist the Northern Territory Mango Industry Association (NTMIA) to develop a communications plan to inform members, government and stakeholders about its business and to promote to non- members the benefits of joining it.
Background:
NTMIA identifies its communication as weak in its Strategic Plan for 2003-06. It also identifies low “grower acceptance” of NTMIA business and “not enough members”.
One of its key strategies is to “create acceptance by, and support of, all stakeholders”. One of its key goals is to ensure that “NTMIA maintains good communication with members and stakeholders”.
215 Horticulture
In June 2004, NTMIA set up a committee to develop a communications plan.
Results:
A committee comprising of NTMIA board members and the department’s liaison officer was formed.
A draft communications plan was submitted to the NTMIA board and was accepted.
NTMIA distributes a quarterly newsletter to members and stakeholders.
NTMIA is driving the communication process.
PROJECT: Mango Industry Skills Survey and Audit 2004
Project Officer: D. Hamilton
Location: Berrimah Farm and the NTHA Office
Objective:
To assist the Northern Territory Mango Industry Association (NTMIA) to identify the training needs of growers through a survey and audit of skills and knowledge.
Background:
In 2002 an attempt was made to survey NTMIA members to identify their skills needs. The project was abandoned due to a lack of resources. In July 2004 the project was implemented by the department on behalf of NTMIA in line with the requirements of the NTMIA Strategic Plan 2003–06. The results of the survey and audit will allow NTMIA to tailor specific training needs for its members in the hope of improving enterprise profitability.
Results:
Approximately 30% of members responded to the survey.
Results of the survey will be presented at the NTMIA pre-season meeting in August 2005.
Results will be reported in the next Technical Annual Report after industry endorsement.
216 Technical Annual Report 2004-05
PROJECT: The 2004 Sea-freight Trial of Mangoes from Katherine to Europe
Project Officers: C. Wicks, J. Bird, T. Maddern and R. Renfree
Location: Katherine Research Station (KRS)
Objective:
To assist Katherine mango growers to export mangoes to Europe by sea using modified atmosphere containers.
Introduction:
In 2003 a group of Kununurra growers invited a group of Katherine growers to join them in a trial to export mangoes to Europe by sea. During 2003 Katherine growers conducted a simple farm audit and provided fruit for be assessment during long storage (over 30 days).
The audits and assessments indicated Katherine fruit was suitable for a sea-freight export trial. In 2004, Katherine and Kununurra growers agreed on the role of Katherine growers and the commercial relationships involved.
Activities
The original plan was for two containers, one each from Katherine and Kununurra. Each container was to be a ‘controlled atmosphere’ refrigerated unit capable of holding up to 20 international pallets of 140 (5 kg) trays of mangoes. These were to be sent out a week apart with most of the logistics being handled by the project officer, Jill Parker, who was based in Kununurra. The logistics included sending the Katherine fruit out through Fremantle without obtaining seed weevil free status.
The role of DPIFM staff in this exercise was to provide limited administrative assistance plus (export specific) local advice and pre-harvest fruit quality assessments as well as to assist the project team during the export process. Another round of static (i.e. long-term) fruit studies was to be carried out. Another Katherine-based study was planned on the effectiveness of Amistar applied pre-harvest to control stem end rot.
KRS staff met all commitments. It should be noted that the amount of time and resources that was eventually committed to this project was much higher than originally expected. Preliminary outcomes of the static trial and the use of Amistar by KRS plant pathologist Shamsul Bhuiyan are reported elsewhere (see the Resource Protection Section of this Report).
Up to now the total time commitment to the sea-freight project was about 300 hours. The time commitment by DPIFM staff to the export process was about 150 hours. Such an amount of commitment was not predicted; however, the outcomes will hopefully justify the strong effort of DPIFM staff.
Outcomes
Over 25 tonnes of Katherine mangoes were exported by sea and air through this trial. The fruit went out mainly in two separate containers - one through Darwin with the support of the NT Freight Council and the other through Fremantle.
The commercial return from this exercise was not as high as had been hoped. Agriculture WA and participating growers will submit a report on the entire project in late 2005. At a meeting in early 2005
217 Horticulture facilitated through a grant from the National Food Industry Strategy, growers decided to trial a full commercial venture in the 2005 season.
PROJECT: Improving the Sustainability of the Katherine Horticultural Industry through Local Best Practice Groups
Project Officer: J. Bird
Location: Katherine Region
Objectives:
To facilitate the improvement of horticultural crop management practices in the Katherine region.
To promote the local best management practice group’s activities in the Katherine region.
Introduction:
On 19 February 2005, about 35 invited stakeholders in the Katherine horticultural industry discussed and updated a plan for the ‘Future Directions for Katherine Horticulture’. One of the strategies was a holistic approach to farming in the Katherine region to support the continuation of best practice groups, research and demonstration plots.
Activities
Irrigation management – on farm tensiometer set up and help
A series of on-farm workshops were held in July 2004 attended by 32 growers. A discussion group format was used with growers learning from each other as well as from the invited expert. Each session was held on a farm, beginning with an orchard walk, and finishing with a BBQ. There were five follow up farm visits for irrigation assessment.
Harvest labour strategy meetings
A meeting was held in conjunction with NTMIA where 30 growers attended. Ten growers received additional management training. Information was provided on labour recruitment and related issues.
Weed issues
This is ongoing and growers are referred to the Department of Natural Resources, Environment and the Arts’ Weeds Branch new regional weeds strategy.
Farm finance workshop – David Harris
A workshop was held on 15-16 February 2005 which was attended by 30 growers.
Future directions planning meeting
The meeting was held on 19 February 2005 which was attended by 35 growers. An updated document on Katherine Horticulture’s future was developed.
218 Technical Annual Report 2004-05
Insecticide resistance management strategy
A strategy was developed in conjunction with Entomology for melon growers in the Katherine region and was completed in April 2005. This was designed to prolong the usefulness of chemicals available to growers by reducing the likelihood of resistance. Growers will be working together to implement this strategy.
Farm budgeting workshop
A series of basic and advanced workshops were held on 22-23 June 2005 where six growers attended the basic session and five the advanced session. The aim was to help growers achieve a better understanding of farm budgeting practices which may lead to increased viability.
Results:
The local best practice group activities have been successful in several ways. There is evidence that the major objective of improving horticultural crop management practices in the region has been achieved. Improved irrigation practices, for example, have increased production and/or quality for several growers.
Local best practice group activities have gained popularity among growers. The evaluation process has shown that they enjoy the informal learning process, the social aspects, seeing what other growers are doing on their properties and learning from their peers. The Katherine horticultural industry shows signs of unity among growers, which is not often seen. The local best practice groups are helping Katherine horticultural producers to work together more effectively.
219 Horticulture
Program: Indigenous Horticulture Development
PROJECT: Community Gardens
Project Officer: C. Kelly
Location: Berrimah Farm
Objective:
To encourage horticulture development in indigenous communities by facilitating the establishment of community/market gardens.
Background:
In 2005 the NT Government’s Indigenous Economic Development (IED) strategy was launch. As a part of this strategy the Horticulture Division of DPIFM developed a program to increase the indigenous community’s and the individual’s involvement and participation in horticultural enterprises. The community gardens project is part of this program. It is the first step in the horticultural economic development of indigenous communities.
The project has demonstrated a cooperative working relationship between the Territory Government and the Commonwealth Government under the umbrella of the new arrangements in indigenous affairs. An example of this is the establishment of a community garden at Emu Point. The technical assistance is provided by DPIFM and the financial resources are provided by the Commonwealth.
Activities
Since the commencement of this project in February 2005, a program of community visits has been undertaken. Initially, visits are made to communities expressing an interest in developing community/market gardens. Fourteen communities have been visited to date with a further five showing interest. Visits will be scheduled soon.
The project has focussed on establishing a pilot market garden at the Emu Point community (320 km south- west of Darwin). According to the new arrangements in indigenous affairs, the Emu Point community has signed a shared responsibility agreement (SRA) with the Commonwealth. A production system for the market garden has been developed and is in the process of being implemented. This pilot project will provides valuable information on the possibilities and challenges of establishing and maintaining market gardens in remote indigenous communities.
The IED project contributed funds to the Grow to learn, learn to grow project which has established small vegetable plots in indigenous community schools in the Katherine region.
A number of leaflets are being developed which use culturally appropriate language to describe the step by step process from determining the feasibility of gardens to establishing and maintaining them.
Information is being gathered on opportunities and obstacles to horticulture development in indigenous communities of the Northern Region. It is envisaged that the information gathered in the first year of the project will lead to a more refined strategy and more effective delivery of service in the future.
220 Technical Annual Report 2004-05
Results:
Fourteen communities/outstations were visited. Of these seven are currently undertaking some form of horticultural activity.
Many community/market gardens are in the process of establishment at Emu Point community. Fifteen individuals at Emu Point have enrolled for a Certificate level 1 in horticulture to be delivered on location by remote trainers.
Marthakal Homelands and Elcho Island are in the process of developing an SRA which includes the establishment of a market garden and horticulture training for six individuals.
221 Horticulture
Program: New and Improved Products
PROJECT: Improved Mango Varieties for the NT
Project Officers: G. Azam, T. Maddern, C. Wicks and R. Renfree
Location: Katherine Research Station (KRS)
Objective:
To test in the field mango varieties developed and identified in previous breeding work at KRS.
Introduction:
We report here on a component of this trial that aims to rapidly screen several new Australian and international cultivars under Katherine environmental conditions for their suitability to supply both domestic and international markets.
Method:
The mango cultivar/advance selections planting at KRS consisted of two to four trees of 12 cultivars randomly distributed within the block. Trees were spaced 8 m x 6.5 m. The cultivars Neldica, Heidi, Joa, Chene and E10-5/3 were planted on 24 May 2001 (see Table 1). The cultivars R2E2, Celebration and Kensington Pride (KP) were planted on 5 June 2001. Each of the R2E2, Celebration, N10E10, Neldica, E10- 5/3, KP, Chene, Joa, Heidi, and N10E56 cultivars has four trees. Each of the N6E35 and N8E54 cultivars has two trees (see Table 1). The first significant flowering occurred in 2004 and some preliminary harvest data was collected on 29 November 2004. The weight of “ground” (over mature and fallen) fruit, marketable fruit and unmarketable fruit was recorded and combined for each cultivar to derive the total yield for each cultivar.
Results:
The cultivars that produced the best average marketable fruit were Heidi, Joa, N6E35, N8E54 and Celebration. The cultivars that produced the highest average total yield were Heidi, N8E54, Joa, N6E35 and N10E10. The fruit of Chene was completely unmarketable due to extreme “warty” skin. Cultivars N10E10 and N8E54 appear to mature earlier than Kensington Pride as demonstrated by the number of “ground” fruit at harvest.
Table 1. Mango cultivar yield data, KRS November 2004
Cultivar Tree Av. fallen fruit Av. marketable Av. unmarketable Av. total no. * (kg/tree) (kg/tree) (kg/tree) (kg/tree) R2E2 4/4 0.2 9.6 0 9.8 Celebration 4/4 1.2 17.5 0 18.7 N10E10 4/2 15.3 6.6 0 21.9 Neldica 4/3 2.1 12.5 0 14.6 E10-5/3 4/4 1.9 15.9 1.1 18.9 Kensington Pride 4/4 1.0 11.2 0 12.2 Chene 4/4 0.8 0 5.1 5.9 N6E35 2/2 3.0 22.4 0 25.4 Joa 4/4 0 26.7 0.2 26.9 Heidi 4/3 0.2 31.6 0 31.8 N8E54 2/1 11.1 20.3 0 31.4 N10E56 4/4 5.7 3.9 0 9.6 * Tree no. e.g. 4/3 = 4 datum trees/cultivar with 3 of those 4 carrying fruit 222 Technical Annual Report 2004-05
Conclusion:
This was the first harvest. Another two to four harvests will be observed. The cultivars with the highest combined average marketable fruit weight and total yield were Heidi, Joa, N8E54 and N6E35. In future seasons we plan to quantify fruit maturity over time with dry matter testing and continue yield and quality assessments. We would like to thank Jeremy Bright, former Research Horticulturist for planning and establishing the planting and Birdwood Nursery, Nambour, Qld. and Ken Raynor, Nurseryman, Katherine, for supplying trees.
PROJECT: Northern Australia Cocoa Development (RIRDC Project DAQ-256A)
Project Officers: C. Wicks, A. Gonzalez, C. Kelly, R. Connolly and L. Chidwick
Location: CPHRF
Objectives:
To generate an in-depth knowledge of cocoa production in northern Australia.
To refine an economic model for cocoa production with the aim of determining the economic viability of cocoa production in northern Australia.
In late 1997, Cadbury Schweppes Australia approached the then DPIF, Agriculture WA and QDPI with a proposal to commence a collaborative feasibility study to develop a cocoa industry in northern Australia. Cadbury Schweppes is concerned that the increasing demand from Eastern Europe and China, combined with the continuing problems with supply from traditional cocoa growing areas may lead to a shortfall in production. Currently cocoa prices are rising as forecast.
Method:
After various study tours and an economic analysis by an independent consultant, a number of meetings were held attended by representatives from DPIFM, Cadbury Schweppes, the Rural Industries Research and Development Corporation (RIRDC), QDPI&F and the WA Department of Agriculture. It was agreed to form the “North Australia Cocoa Development Alliance”, which would coordinate all activities, including future commercial development, subject to feasibility of the crop. It was agreed that DPIFM would be directly involved in cocoa yield evaluation and clonal introduction projects.
Results:
A marked seasonal trend in cocoa pod production is clearly emerging. After two complete years of production, it appears that pod yield is generally associated with the build-up, reaching maximum yield towards December/January and declining very sharply by April/May. Under the experimental conditions on which yield from four hybrids have been evaluated in the NT, there are no differences in pod yield between hybrids.
Pod size is still a matter of concern in the NT, as pods tend to be small. A seasonal trend in pod size indicates that smaller pods are produced during the months where yield is the highest. So far, there are no apparent differences in pod size among the four hybrids under evaluation.
Some trial personnel changed during the year. Dr Gonzalez left the Department and moved overseas. He will continue to contribute to the analysis of the data. Mr Kelly has taken up a different position in the Department.
223 Horticulture
The funding for the north Queensland portion of the project has been extended for two years in conjunction with the start of a commercial cocoa industry in the area. However, the NT project was not extended as yields did not increase to commercial levels. Savings in project funds will allow for a final harvest and removal of the trees late in 2005. A final report will submitted at that time.
PROJECT: New Heliconia and Ginger Varieties for the Ornamental Industry
Project Officers: D. Marcsik, M. Hoult, C. Ford, A. Wilson (Horticulture Apprentice) and M. Hearnden (Biometrican)
Location: Berrimah Farm and Commercial Nurseries
Objective:
To promote market opportunities for the ornamental industry by providing new and unique Zingiberale (heliconia and ginger) varieties over the next three years.
CURCUMA
Introduction:
Curcuma breeding is a continuation of the ginger breeding work that started in 1999. The primary focus of this breeding program was to develop new commercial cut-flower varieties, which resulted in six new commercial Zingiber spectabile varieties and a selection of Etlingera hybrids. However, the focus of the current Curcuma work is to develop a range of commercial ornamental varieties, both as cut-flowers and potted colour plants. Curcumas as a potted colour plant, has had more exposure on the Australian market and significantly greater exposure on the world market. As a cut-flower it is recognised as exotic and unusual, but having a short vase-life. A brief description is provided for the next phase of the Curcuma work on hybrid evaluation and selection to identify promising commercial cut-flower and potted colour types.
Method:
A field trial was established at Berrimah Farm to evaluate those families which had been selected as candidates for the cut-flower industry. The trial was a randomised complete block with five replications, each replication consisting of 28 families and four self-crossed parents, with one to seven hybrid seedlings to a family represented in a replication. Hybrid seedlings with visible leaves were planted in December 2004 in mounded rows 2.5 m apart and 50 cm within the row. Fertiliser was applied pre-plant at 500 kg/ha NPK Blue, 500 kg/ha single super phosphate, 1000 kg/ha lime and 1000 kg/ha gypsum. Irrigation was applied by T-tape at 5 L/m/h, twice a day for 2 hours. Plants were fertigated weekly throughout the flowering season by injecting through the T-tape 1.5 kg/ha/week urea and 1.2 kg/ha/week KNO3. Preliminary observations were made on inflorescence colour and form, stem length, hybrid vigour, plant habit and health, and flowering time. In April 2005, the NT cut-flower group (NTCFG) conducted a field walk and selected promising hybrids.
Advertisements were made for an expression of interest to select suitable nurseries to participate in the commercial evaluation of selected Curcuma hybrids, as promising potted colour plants. Nurseries were selected primarily on their expertise in potted colour plant production and their established commercial markets.
224 Technical Annual Report 2004-05
Results:
Preliminary observations indicate that hybrid vigour, rhizome health and performance of most hybrids under the full sun were generally very good. There were some losses on some sites, which were replaced with available hybrid seedlings of the same family or left vacant if no plants were available. Over 80% of the planted hybrids flowered in the first season with some hybrids achieving yields of up to 13 inflorescence stems. Flowering started at the beginning of January and continued through to the end of April, with heavy flowering occurring between February and March. During the NTCFG field walk, around 25 hybrids were selected by the group. Figure 2 shows some of the group’s most liked Curcuma hybrids from the field trial.
A commercial production nursery in Darwin, Queensland and New South Wales was selected to evaluate the other group of Curcuma hybrids. Each nursery received a select number of families, and where there were available hybrid numbers, the same family was allocated to each nursery. For the first season, only one visit was conducted to the Darwin nursery to observe and record those hybrids that were flowering. The Queensland nursery reported a few hybrids flowering but the NSW nursery did not report flowering.
Conclusions:
From the preliminary observations for the first Curcuma hybrids to flower this season, it appears there is potential to develop promising hybrids with improved hybrid vigour, range of inflorescence colour and form, and extended flowering. Significant improvement in hybrid vigour was seen in particular hybrids, which produced a large number of shoots and flowering stems. Furthermore, there were particular hybrids that performed well under the full sun, compared with their parents, which required at least 50% shade to grow well.
At the next flowering season an intensive evaluation and screening of the Curcuma hybrid will be conducted to determine promising cut-flower types, as well as, promising potted colour plant types. In addition, visits to the three nurseries to screen and gather data on those hybrids is planned for the second flowering season.
225 Horticulture
Figure 1. A selection of the NT cut-flower group’s most liked Curcuma hybrids
226 Technical Annual Report 2004-05
ZINGIBERALE (HELICONIA AND GINGER)
Introduction:
Pollination studies are conducted on a regular basis during flowering time on the different Zingiberale accessions, to test for pollen viability and cross-ability. This information is collated together with information from previous screening work conducted on the accessions maintained at Berrimah Farm. This will assist with further selection and breeding work. Crosses that result in seed-et and successful germination are of high value with regards to generating new germplasm material and potentially something with commercial ornamental promise. This report discusses the pollination studies conducted during 2004-05 and recent Zingiberale introductions at the Berrimah Farm horticulture block.
Method:
Selected crossings were performed on a number of Zingiber accessions to determine pollen viability and to test for cross-ability. Where crosses were successful the seeds were harvested soon after the capsule split open, and were sown in an open media of coco-peat:perlite (50:50). Date of germination and numbers germinated were recorded. Later, germinated seedlings were potted into 900 mL tree tubes using a potting media consisting of coco-peat:perlite (50:50) mixed with 6 g/L dolomite, 3 g/L 15N:4.4P:10K, six month control release fertiliser, 1 g/L FeSO4, 1 g/L Micromax ® and 1 g/L ZnSO4. Tissue culture plants and rhizomes donated by Tony Osborne from Kuranda Range Nursery were also potted up using the same growing media.
Results:
Table 1 lists the new accessions of Zingiberaceace and heliconia introductions into the ornamentals project. In general, most seeds germinated, except for Zingiber sp. ‘No.2’ and Zingiber niveum that have not yet germinated. In addition, one of the Heliconia colgantea plants flowered while in the pot at the Berrimah Farm nursery (see Figure 2).
Figure 2. Heliconia colgantea inflorescence
227 Horticulture
Conclusion:
During 2004-05 a number of Zingiber hybrid and self-crossed seedlings were generated from the pollination studies. In addition, a number of open-pollinated seedlings of Heliconias and Etlingera, and new accessions of Curcumas have been introduced. These accessions are currently being maintained at the Berrimah Farm horticulture block, with the aim of reviewing and selecting with the NT cut-flower group those Zingiberale genera that warrant commercial development.
DPIFM Horticulture acknowledges the generous supply of plants by Tony Osborne from Kuranda Range Nursery, and donation of seeds by Bruce Dunstan and Endre Guttmann.
Also, thanks to Sharon Wilson at the George Brown Botanic Gardens for allowing us to collect Heliconia seeds from the gardens and Neal Witham for the Etlingera seeds.
228 Technical Annual Report 2004-05
Table 1. Zingiberale introductions during 2004-05
Zingiber Accession Cultivar/ selection Source Status Zingiber hybrids Z. wrayii x Zinger sp. ‘Long Jowie’ hand-crossed Seedlings @ BARC nursery at BARC Z. wrayii Selfed cross at BARC Seedlings at BARC nursery Z. pachysiphon Selfed cross at BARC Seedlings at BARC nursery Zingiber sp. ‘No. 2’ Selfed cross at BARC, ex B. Dunstan Seed sown; no germination Z. niveum Selfed cross at BARC, ex Bangkok Seed sown; no germination Z. collinsii ‘Silver streaks ex KRN, Tony Osborne TC plants, potted on at BARC nursery Z. niveum ‘Milky way’ ex KRN, Tony Osborne Rhizomes, potted on at BARC nursery Z. parishii ex KRN, Tony Osborne TC plants, potted on at BARC nursery Z. malaysianum sp. nov ‘Midnight’ ex KRN, Tony Osborne TC plants, potted on at BARC nursery Zingiber hybrids ‘Singapore gold’ x ‘Apricot’ and Hybrid plants currently being ‘Apricot’ x Singapore gold’ hand-crossed at commercially tested on grower’s BARC property. Heliconia Accession Cultivar/ selection Source Status H. colgantea ex Endre Guttmann, Puerto Rico Seed given to DPIFM. Seedlings potted on at BARC nursery H. chartacea ‘Sexy pink’ Various locations ex. George Brown Botanical Open-pollinated seed harvested. Gardens, CPHRS, cut-flower farm Howard Seedlings potted on at BARC nursery. Springs Curcuma Accession Cultivar/ selection Source Status C. alismatifolia ‘Kimino pink’ ex KRN, Tony Osborne TC plants, potted on at BARC nursery C. aurantiaca ‘Royal pink’ ex KRN, Tony Osborne TC plants, potted on at BARC nursery C. roscoeana ‘Jewel of Burma’ ex KRN, Tony Osborne TC plants, potted on at BARC nursery Other Gingers Accession Cultivar/ selection Source Status Etlingera elatior var. Alba ex Neal Witham Open-pollinated seeds harvested from inflorescences. Seedlings potted on at BARC Alpinia sp. New Georgia ‘Pink ex Bruce Dunstan Seeds given to DPIFM, no germination coral’ yet. Riedellia sp. ex Lae Botanical Gardens Open-pollinated seeds harvested from inflorescence, no germination yet.
229 Horticulture
PROJECT: Sub-tropical Germplasm Assessment - Citrus Evaluation Trial
Project Officers: I. Broad, D. Salter and D. King
Location: Alice Springs Region
Objective:
To evaluate the suitability of navel, lemon and mandarin cultivars for growing in Central Australia.
Introduction
Trial plantings of lemons, mandarins and navel oranges were established at the Arid Zone Research Institute (AZRI) in 1997 and Ti Tree Research Farm (TTRF) in 1999 as a means of determining suitable cultivars for possible commercial production in Central Australia.
Method:
AZRI planting
A trial plot of navel oranges and lemons was planted in 1997. The plot of navel oranges consisted of five cultivars, Leng Navel on Swingle, Washington Navel on Citrange, Washington Navel on Troyer Citrange and two later maturing varieties, Barnfeild Summer navel on Trifoliata and Toc Summer Navel on Citrange. Lemon varieties consisted of Fino, Verna, Lisbon and Eureka all grown on Citrange rootstock.
Selections of mandarin cultivars were also planted in early 2000. These cultivars consisted of Ellendale on the rootstock Swingle, Ellendale on Troyer Citrange, Imperial on Sweet Orange and Imperial on Cleopatra. Many of these were either damaged or destroyed by abnormally severe frosts during the 2002 winter period. Consequently, half of the 20 mandarin trees being trialled at AZRI were removed. Replacements were selected and planted in the spring of 2003. The trial planting now consists of Ellendale on Citrange, Ellendale on Troyer Citrange, Imperial on Swingle, Imperial on Troyer and Imperial on Cleopatra.
TTRF planting
A citrus evaluation trial was also established at TTRF in 1999, about 200 km north of Alice Springs. The varieties and rootstock combinations being assessed are Washington and Leng Navel both grown on Troyer Citrange and Rough Lemon. Lemon varieties include Eureka and Verna both on Benton Citrange and Fino on Troyer Citrange. Mandarin varieties include Imperial on Cleopatra, Troyer Citrange, Swingle and Rough Lemon rootstocks and Ellendale on Swingle. A Tangelo variety, Minneola on Troyer Citrange rootstock is also being trialled.
Method of assessment
Assessments are made on overall fruit quality and yields. Five fruits from each tree are selected and weighed; the diameter and rind measurements are taken followed by a seed count. The fruit is then juiced and juice percentage is calculated. Juice is then measured for Brix and acid levels. Results were compared with national standards. Total fruit counts and weights are recorded and overall yields are calculated for each cultivar and rootstock combination.
230 Technical Annual Report 2004-05
Results:
Navel oranges
This is the fourth and final year of assessment for navel orange cultivars at AZRI. Table 1 and Figure 1 present the average maturity and yield information per scion/rootstock combination calculated using the past four seasons’ data. These two factors are used as the primary indicators of a cultivar’s overall performance.
In Table 1, two of the six cultivars have been highlighted, Washington Navel on Troyer Citrange and Leng Navel on Citrange. These two cultivars consistently produced higher quantities of fruit and reached maturity earlier than any other cultivars. This suggests Washington Navel on Troyer Citrange and Leng Navel on Citrange may be suitable for commercial production in Central Australia. The next step in the evaluation process will be to determine if there is any market advantage to citrus production in Central Australia.
Average Navel Yields Per Tree (Kg)
50
45
40 Washington Navel/ Troyer Citrange (old) 35 TOC Summer Navel/ Citrange (old) 30 Leng Navel/ Swingle (old)
25 Leng Navel/ Swingle (Kg)
Washington Navel/ 20 Citrange
Barnfield Summer 15 Navel/ Trifoliata
10
5
0 Av. Yield (Kg)
Figure 1. Average yields per tree per year
Table 1. Average juice (%)and Brix/acid ratios for navel oranges
Variety/ rootstock Av. juice (%) Av. Brix/ acid ratio Washington Navel/Troyer Citrange 37 15 Toc Summer Navel/ Citrange 34 13 Leng Navel/ Swingle 37 14 Washington Navel/ Citrange 35 14 Barnfield Summer Navel/ Trifoliata 34 11 Nations standard = 33% juice or above
TTRF navel orange results
Two years of maturity data has been collated from trial navel oranges to date. A further two years data will need to be collected before a worthwhile assessment can be made on the suitability for possible commercial production in the Ti Tree area. Preliminary results indicate all trial navel cultivars, in particular Washington Navel on Troyer and Washington Navel on Rough Lemon rootstock, may be suitable for possible commercial production in the Ti Tree area.
231 Horticulture
Lemons
From trial results, observations can be made on the performance of individual scion rootstock combinations. Taking both the average maturity results and average yield information for each of the five cultivars into consideration it appears as though Eureka on rootstock Citrange is the best all round cultivar. The average yearly fruit yields for the Eureka cultivar as shown in Figure 3 were consistently 20 to 25 kg more than any other cultivar. This result was also complemented by an acceptable average juice percentage of 36% in March as shown in Figure 2. Results indicate selected lemon cultivars such as Eureka on Citrange may be suitable for commercial production in Central Australia. The next step in the evaluation process will be to determine if there is any market advantage to citrus production in Central Australia.
Average March Juice Percentages
45
40
35
30
Lisbon/ Troyer Citrange 25 Lisbon/ Citrange
% Eureka/ Citrange 20 Fino/ Citrange Verna/ Citrange
15
10
5
0 Average juice percentage National Standard = 33% or above
Figure 2. Average March juice percentage per cultivar
Av. Lemon Yields per Variety/ Rootstock (Kg)
160
140
120 Lisbon/ Troyer Citrange (old) 100 Lisbon/ Citrange (old)
Eureka/ Citrange (old) 80 Fino/ Citrange Weight Kg Weight Verna/ Citrange 60 Lisbon/ Citrange
40
20
0 Av. Total Weight (Kg) Variety/ Rootstock
Figure 3. Average total fruit weight per tree per year
232 Technical Annual Report 2004-05
TTRF lemon results
Two seasons’ worth of maturity and yield data has been collected from trial plantings of lemons at TTRF. Initial results indicate selected lemon cultivars may be suitable for commercial production in the Ti Tree area. Eureka on Rough Lemon, Fino on Benton and Lisbon on rootstock Troyer meet Australian maturity standards by mid March. The remaining trial cultivar Verna on Benton rootstock performed poorly reaching acceptable maturity four weeks later than the above varieties.
Mandarins
Maturity and yield data was collected from the mandarin evaluation trial for the first time this season. However, it is still too early in the evaluation process to make any comment on the suitability of cultivars. A further three years worth of data will need to be collated before any meaningful recommendation can be made.
TTRF mandarins
The TTRF mandarin cultivars primarily consist of Imperial mandarin on a variety of rootstocks including Cleo, Troyer, Swingle and Rough Lemon. All four of these scion/rootstock combinations performed well over the past two seasons with all meeting Australian maturity standards by mid April. A further two years worth of maturity and yield information will need to be collected before a complete assessment can be made on cultivar suitability.
Pests and diseases
Large numbers of oriental spider mites were discovered in May of this year on approximately 80% of trial navel orange and lemon cultivars. Since their discovery an appropriate treatment was sourced and applied. Since then, mites have all but disappeared.
TTRF pests and diseases
The oriental spider mite was discovered on selected navel orange and lemon cultivars within TTRF trial plantings. Measures were immediately taken to address this problem. Foliar sprays of Natrasoap and Spraytech oil were applied several times during the season to eradicate the problem.
Large numbers of scales were discovered on mandarin cultivars and on selected navel orange and lemon cultivars. The infestation was remedied through the application of foliar sprays of Natrasoap and Spraytech oil.
Summary
This was the fourth and final year of assessment for both navel orange and lemon cultivars.
Results indicate selected navel orange and lemon cultivars may be suitable for commercial production in Central Australia.
The next step in the evaluation process will be to determine if there is any market advantage for citrus production in Central Australia.
Maturity and yield data was also collected from the mandarin evaluation trial for the first time this season.
A further three years worth of maturity data will need to be obtained from the mandarin evaluation trail before a meaningful assessment can be made.
233 Horticulture
Future work
Navel oranges and lemons
Write up a complete report detailing trial results and making recommendations on navel orange and lemon cultivar suitability to Central Australian conditions.
Determine if there is any market advantage to citrus production in Central Australia based on current market trends.
Mandarins
Continue assessment of mandarin cultivars for a further three years.
Future work at TTRF
Continue assessments of the citrus cultivars for another two years.
Maturity testing to commence earlier next season to better identify possible early maturing varieties.
PROJECT: Sub-tropical Germplasm Assessment – Evaluation of Stone and Pome Fruit in Central Australia
Project Officers: D. King, I. Broad and D. Salter
Location: AZRI and TTRF
Objective:
To research, identify and evaluate suitable sub- tropical crops for production in Central Australia
Introduction:
At present, there are no commercial plantings of stone fruit in the Alice Springs Region. There are however, indicators that potential markets for Central Australian stone fruit may exist in the Northern Territory and interstate.
Research plantings of stone fruit were established at AZRI in the past. Initially these plantings grew well and produced satisfactory crops; however, they eventually became unthrifty and had a short life span. The rootstock used for these earlier plantings was Nemaguard. This rootstock was unable to adapt to the high pH levels of the soils, and the high soil temperatures experienced through the summer period.
Therefore, there still exists a need to identify, research, and evaluate sub–tropical crops suitable for production in Central Australia.
Method:
New plantings were established at AZRI in 1996, 1997, 1998 and 1999 consisting of peaches, nectarines, apricots and plums. Several high and medium chill varieties were removed in September 2002. There are presently seven varieties of apricot, four varieties of peach, and one variety of nectarine planted.
A planting was also established at TTRF in 1998. This planting includes nine varieties of peach, four varieties of nectarine and two varieties of apricot. These plantings had their first crop in 2002. Several
234 Technical Annual Report 2004-05 varieties were removed in 2004 due to varying weather conditions and poor performance. The Ti Tree plantings now consist of three peach varieties, two varieties of nectarine and two apricot varieties.
The main rootstock used on low chill selections of peaches and nectarines is Bright’s Hybrid, (a peach/almond hybrid). This rootstock has nematode resistance and a tolerance to high soil temperatures and pH levels. Apricot varieties are grown on plum rootstocks, Microbalan 29C and Marianna.
The aim of these plantings is to evaluate the potential for the commercial production of dessert stone fruit in Central Australia. This will include the evaluation of a range of stone fruit types and varieties with varying chill requirements on a range of rootstocks.
Sugar content of the fruit assessed was measured with a refractometer. The readings, in degrees brix, also gave indications to the relative maturity of the fruit. The refractometer readings were acquired by squeezing juice from the fruit after it had been cut into sections.
Results:
The removal of some 70 high and medium chill varieties, including many used in previous research has meant the 2004 season recorded significant changes in the data collated when compared with the previous season. Results were affected by heavier pruning, more intense thinning, later than normal frosts and varying weather conditions. Fruit assessments, including weights, fruit counts and diameter measurements were carried out on the remaining varieties in the 2004 season. Sugar levels in all varieties assessed were well in excess of the Australian standard of 11.0 (Australian Horticulture Corp., 1999)
Peaches
In 2004 flowering for low and some medium chill varieties occurred from late July through until mid September, while harvest commenced in early November and concluded in mid December (trees were harvested on average twice a week during this period). The remaining medium chill varieties flowered later with harvest completed by the end of December. Flordagold, being the only variety remaining from previous years’ trials, produced an average of 45.07 kg per tree with an average brix of 15.1. Of the remaining varieties, Tropic Snow produced an average of 64.04 kg, per tree with a brix average of 14.3 and Earligrand produced 25.28 kg average per tree with a 16.3 brix average while Aztec Gold and Tropic Beauty produced very few fruit.
Nectarines
Rose Diamond was the only variety remaining in the planting from previous years.
Flowering for the nectarines in 2004 commenced in early August, and continued until mid September. Harvest commenced in mid November and continued until the end of the month. Fruit size was also down on previous years
Apricots
In 2004, Trevatt and Moorpark Early varieties were the only producers. Apricots need a longer period of time to establish and four other varieties, Castlebrite, Taminick Gold, Goldrich and Rival, planted in late 1999 are expected to carry a light crop next season.
Tree management
Nutrition
Results from leaf nutrient analysis in 2004 have indicated low levels of zinc throughout the planting. A zinc spray at the appropriate time will assist in maintaining levels of this nutrient. Copper and calcium levels were 235 Horticulture marginal. Copper oxychloride sprays have been used to overcome the copper deficiency problem. A light side-dressing of ammonium sulphate or ammonium nitrate will help to keep nitrogen at acceptable levels. Sodium and chloride levels were also very high in some varieties. Uptake of salt varies between rootstocks. A regular leaching program is addressing the problem.
Birds
The use of a gas powered ‘scare’ gun has reduced the amount of damage caused by birds as the fruit ripens, which is a major problem that has occurred in the past at AZRI. Early maturing crops however, still incurred heavy losses. There was no apparent fruit fly damage.
Summary
Overall, commercial yields of medium and low chill nectarines and peaches were much lower than in previous years. One of the four varieties of apricots planted in 1998 produced a small crop. Fruit fly infestation was negligible and severe bird damage affected marketable fruit.
Future work
A further 12 months’ evaluation for apricot varieties planted at AZRI in 1998-99 is planned. Then plantings will be rationalised according to available resources.
A technical report will be prepared on the viability of stone fruit production in Central Australia.
Pome fruit
Summary
A small crop was produced in 2004. The performance of Pink Lady (planted in 1997) and Sundowner (planted in 1998) varieties will continue to be monitored at AZRI for another year. The TTRF varieties have been removed. The trees had poor growth due to nutrition and heat stress.
Two new varieties (Pink Lady/M9) and (Galaxy/MM106) were supplied by from orchards in South Australia and planted in three rows of 20 trees of Galaxy and one row of 20 trees of Pink Lady in September 2004.
Future work
To produce a larger crop on the older varieties, a plant growth regulator will be trialled and pruning, nutrition and irrigation programs will be intensified at AZRI.
With an increase in nutrition and irrigation programs along with the pruning regime, evaluation of these plantings will continue for another year. It is anticipated that new pollinators will be acquired to replace Granny Smith.
In conjunction with the supplier a nutrition and management program has been set in place for the new varieties. This program will be monitored for a year.
TTRF stone fruit harvest 2004
All plantings established at TTRF in 1998 are low to medium chill varieties and came into production during the 2003 season. Only minimal data has been collected at this stage.
236 Technical Annual Report 2004-05
Peaches
All the three remaining varieties of peaches produced fruit during the 2004 season. Flowering for the fruit bearing varieties commenced in mid July and extended until early September .The varieties with the highest yields and best quality fruit were Aztec Gold and Flordaglo cultivars. These varieties exceeded accepted Australian sugar standards while fruit size was below market standard.
Nectarines
Of the two varieties of nectarines remaining, only Sunwright produced a small crop during the 2004 season. Flowering in this variety was from mid July until early August, while the remaining variety did not reach 100% flowering until late September. Average fruit size for Sunwrights was very small while sugar levels were well above Australian standards.
Apricots
Both varieties of apricots established at TTRF had delayed bud-burst, bud jump and failed to produce any quality fruit. As they are still in the early stages of maturity, they will need more time to establish.
Tree management
Nutrition
Results from recent leaf analysis indicated slight deficiencies in zinc and sulphur throughout the plantings.
Birds
Bird damage in the early maturing varieties was the only major problem experienced during the 2004 season.
Summary
As the plantings are just reaching production age and only minimal data has been collected, it is hard to make comparisons. However, from the available information, the Aztec Gold, Flordaglo and possibly Earligrand peach varieties look promising if larger fruit size can be achieved.
Future work
As the plantings are still to fully mature, especially the apricots, data will continue to be collected and assessed in the 2005 season.
References
Australian Horticultural Corporation (1999) Product Description Language: Stone fruit.
Australian Fresh Stone Fruit Association
237 Horticulture
PROJECT: Tropical Germplasm Assessment
Project Officer: G. McMahon
Location: CPHRF
Objectives:
To research and identify suitable fruit crops for Top End production.
To evaluate phenology and yield of selected lowland longan varieties and multiply and release to industry those that are suitable.
Longan
The Vietnamese low-land longan (Dimocarpus longan), continues to grow and is being assessed. The trial trees were planted in 1999 with a subsequent planting in January 2003. Five varieties are now planted, Mata Kuching, Xuong com vang, an unnamed variety called ex Vietnam, Long and Tieu la bau.
Irrigation
Last season watering was reduced to 8 L/h/tree for one hour a day during the wet as some trees showed signs of waterlogging. The trees did not show any signs of stress during the dry season due to the reduced amount of water. In fact they grew bigger than in the previous year. The water was increased to 40 L/h/tree for one hour a day when flowering began, but showed no effect on production, only large trees with prolific growth. Dynamic lifter 3:5:5 NPK was applied four times a year at a rate of 500 g/tree, and mulch hay is applied once a year.
Phenology
On the variety Xuong com vang the leaf flushing occurs all year and only slows down during flowering.The other varieties show a defined period when flushing stops and new leaves harden off.
Flowering
The main flowering period for the variety Xuong com vang, begins in late August through to November, with another small flowering in March/April. Flowering has begun in the variety ex Vietnam but has been very sparse with only two trees flowering in September/October. Tieu was planted two and a half years ago and flowered on four occasions during the year, in September/October, January, March/April and again in July.
Figure 1. Longan tree in flower
238 Technical Annual Report 2004-05
Fruit
Some fruit was harvested at the end of January (see Table 1).
Table 1. Comparison of average fruit weight for the last three seasons
Tree ID Variety 2004-05 avg wt/ 2003-04 avg wt/ 2002-03 avg wt/ fruit (g) fruit (g) fruit (g) R3T4 Xuong com vang 12.5 9.4 15.4 R3T6 Xuong com vang 12.5 17.6 14.4 R3T8 Xuong com vang 18.2 17.8 15.6 R3T10 Xuong com vang 14.0 17.6 15.0 R3T14 Xuong com vang 17.4 16.0 R4T8 Xuong com vang 18.3 18.7 R4T14 Xuong com vang 18.5 16.4 R4T17 Tieu 11.6 R5T11 Xuong com vang 17.1 R5T13 Xuong com vang 16.2 R5T14 Xuong com vang 17.5
Yield data will be collected again when more varieties are producing.
Pruning
Due to large growth during the year the trees were heavily pruned in April which reduced their size by two thirds.
Figure 2. The variety Xuong com vang before pruning in April
Note second flowering.
239 Horticulture
Figure 3. The variety Xuong com vang nine weeks after pruning
Not only does pruning reduce the tree size but will also help establish tree shape as trees are multi-stemmed and very unruly. After pruning, growth is very rapid and the trees are in a constant state of leaf flush. Flowering was expected again in September.
240 Technical Annual Report 2004-05
Program: Production Systems
PROJECT: Asian Vegetables – Best Practice
Project Officers: G. Walduck, M. Traynor, J. Thomas, G. Owens, K. Bui (industry- based IDO) and Dr. B Thistleton (Entomology)
Location: Darwin Region
Objective:
To support the Asian vegetable industry and its organisation.
Introduction:
The industry is centred near Darwin with 50+ small growers producing a range of Asian and traditional vegetables for local and capital city markets. The main thrust of work in this area this year has been to support the grower organisation and the industry development officer (IDO) and supply information on better practice farming techniques through grower meetings, field days and printed material.
Activities
Support the activities of Kim Bui, the Vietnamese speaking IDO. Unfortunately, the industry based and DPIFM funding ran out late in 2004 and was not renewed in spite of various attempts led by NTHA. Consequently, the Asian vegetable industry is without an IDO which has significantly curtailed planned work.
Distribute more copies of the English/Vietnamese publication of all current DPIFM printed information on Asian vegetables including the two-poster set of Pests and Diseases of Asian Vegetables. This publication has been well received in the NT and is in strong demand interstate in Asian vegetable growing areas.
Produced a working version of a PC based ‘tool box’ for agricultural pesticides for use in Asian vegetables in the NT in cooperation with Resource Protection. The prototype will be field-tested during the 2005-06 growing seasons.
Okra is affected by mould at the end of the season. A trial was conducted late in the 2004 dry season which confirmed dipping of okra after harvest with sodium hypochlorite solution at 100-400 ppm active would control post harvest moulds and improve appearance at market. This confirmed the results of the original trials conducted in the previous season and reported in the 2003-04 TAR. Storage was at 6ºC in normal packaging. Rates of 100-200 ppm active chlorine gave best visual results. A rate of 400 ppm caused some damage in the longer storage times and Benomyl gave no better results than water as in previous trials.
Snake bean production has been severely affected by Fusarium wilt in recent years with losses of over 70% in severe cases. Cowpea variety ‘Iron’ has been identified as an excellent rootstock for snake bean as it is vigorous, compatible with the current snake bean variety ‘Green Pod Cochin’ and resistant to both Fusarium wilt and root knot nematode, the two most damaging pests of snake bean in the NT.
Two demonstration plots of snake bean grafted onto ‘Iron’ cowpea were established on grower properties. Field walks were associated with each to demonstrate to growers both the resistance to Fusarium wilt and the superior growth and yield of the grafted plants over field planted seedlings.
241 Horticulture
Figure 1. The superior growth and yield of grafted plants on the left compared with the seedling plants on the right
There were plant losses to Fusaruim wilt disease in seedlings and no losses in grafted plants.
A small plot of ‘iron‘ cowpea was established at Coastal Plains Research Station to supply seed for rootstocks as commercial supplies are not readily available in the NT.
Weed control in snake beans at the seedling stage has been identified by growers as an important production issue. A demonstration plot of a pre-emergent residual herbicide was established and proved successful in suppressing most weeds. Sedges were not well suppressed and did not affect growth of direct seeded snake beans. Figure 2 shows the weed suppression after two weeks. Control began to break down after four to six weeks due to the light sandy soils.
242 Technical Annual Report 2004-05
Photo 1: 0 – nil Photo 2: 1 - Stomp® @ 1 L/ha
Photo 3: Stomp® @ 3 L/ha. Photo 4: Nil weed control after five weeks (note weed control in background by Stomp® @ 3 L/ha)
Figure 2. Weed control two weeks after treatments
Bamboo trial work is being completed and data is being collated for a final report. A number of grower field days were conducted to show current bamboo growers the latest results.
243 Horticulture
PROJECT: Taro Fertiliser Rate Trial 2004
Project Officer: M. Traynor
Location: Property of Mr Sok Lee – Darwin River
Objectives:
To establish a fertiliser response trend for “Bun Long” taro under local dry season conditions.
To record the effect of a range of fertiliser inputs on marketable corm yield.
To provide the basis for a sound fertiliser recommendation for current and potential taro growers.
Background:
Recommendations for fertiliser rates for ‘Bun Long’ taro vary widely depending on location and management. Local taro growers are producing good crops with the recommended fertiliser inputs but these rates are speculative and possibly excessive to requirements for optimum marketable yield. This recommendation is tested along with experimental rates to more accurately quantify the nutrient requirement for taro in the Top End dry season environment.
Method:
Planting material
Propagation was done with ‘setts’ which consist of the upper 1 – 3 cm tip sections of sucker corms with 30 – 40 cm of leaf stalk attached.
Trial design
Plants 0.6 m apart.
Twenty four plants per bed.
Eight fertiliser rates randomised over two blocks of four beds.
One row per treatment rate.
Buffer plants at each end of beds.
One buffer row each side of four bed block.
Buffer rows subject to the same rate as adjacent treatment row.
Management
Site pH was adjusted to 6.5 using agricultural lime and standard basal fertiliser was applied to the beds. The trial crop was planted on 19/05/04. Irrigation spray jets were installed between plants so applied fertiliser was adequately watered into the soil. Soil moisture was monitored with tensiometers.
Pest and disease control was performed by the grower as required.
Harvest of plots commenced at 210 days after planting (DAP) and was determined by plant maturity indicators observed by the grower.
244 Technical Annual Report 2004-05
Fertiliser treatments were monitored by leaf nutrient analyses. Samples collected were the second youngest open leaf blade from three designated tagged plants in each treatment. Plants were sampled each month, 10 days after the monthly fertiliser application. The petioles were removed as close as possible to the blade. Leaves were then washed, oven dried, milled and analysed.
Fertiliser treatments
The following fertiliser treatments were the total applications over six months. These were divided into six equal applications, applied monthly for six months after planting. The rates are in kg/ha and were applied as side-dressings using muriate of potash, urea and superphosphate.
20% (100 N, 40 P, 240 K) 40% (200 N, 80 P, 480 K) 60% (300 N, 120 P, 720 K) 80% (400 N, 160 P, 960K) 100% (500 N, 200 P, 1200 K) farmer’s rate 120% (600 N, 240 P, 1440 K) 160% (800 N, 320 P, 1920 K) 200% (1000 N, 400 P, 2400 K)
Data
Monthly leaf nutrient analyses were conducted for each treatment.
Corm number and individual weight per plant were recorded.
Corms were graded to the following standard provided by Taro Growers Australia.
Large: 1.25 kg – 3 kg Medium: 0.75 kg – 1.25 kg Small: 0.35 kg – 0.75 kg
Results:
Due to the limited area available for the trial, the design was restricted to only eight data points and used as a pilot study to determine where the response to fertiliser reached a peak.
Figure 1 shows the predicted market yield response. The equations produced indicate the value of fertiliser where yield is at a maximum for each market grade. There was a poor relationship within the small grade with no significant maximum. The medium and large grades showed loose relationships with maximum yield produced at 104% and 109% fertiliser inputs.
245 Horticulture
Taro grades - predicted means per hectare small medium large 20
y=1455.6999+8.5995*x-0.0393*x^2
15
10 y=918.6979+3.31*x-0.0159*x^2 Tonnes / ha. / Tonnes
5 y=540.0936-1.3082*x+0.0054*x^2
0 20 40 60 80 100 120 140 160 180 200 Fertiliser rates
Figure 1. Taro grade means
Table 1 shows the market yield of the fertiliser rates applied in the trial and shows that the yield response of taro to increasing amounts of fertiliser is not dramatic. The treatment with 60% of the farmer’s rate was sufficient to attain 95% of maximum marketable yield. This data indicates that fertiliser is not a strong determinant of marketable yield in ‘Bun Long’ taro.
Table 1. Taro yield response to fertiliser
N:P:K Treatment Marketable means (tonne/ha) % of maximum (kg/ha) 10 000 plants/ha market yield small medium large total 100:40:240 20 5.16 9.79 16.12 31.07 89.36 200:80:480 40 4.96 10.26 17.37 32.59 93.74 300:120:720 60 4.81 10.60 18.30 33.71 96.97 400:160:960 80 4.70 10.82 18.92 34.44 99.06 500:200:1200 100 4.63 10.91 19.23 34.77 100.00 600:240:1440 120 4.61 10.87 19.22 34.70 99.80 800:320:1920 160 4.69 10.41 18.26 33.36 95.95 1000:400:2400 200 4.94 9.45 16.04 30.43 87.52
Nutrient monitoring
The following charts show the NPK leaf levels for the treatments that produced at least 95% of maximum marketable yield. These levels could be used as a guide to the adequate leaf nutrient concentrations throughout growth. Large amounts of fertiliser, particularly nitrogen, promote excessive above-ground growth and reduce dry matter allocated to the corms and result in reduced yield. Although not presented in this report, the high fertiliser treatments in the trial maintained high leaf nitrogen levels throughout all growth phases including the period of maximum dry matter production and corm enlargement (100 to 130 DAP). This resulted in more dry matter allocation to plant tops at the expense of corm growth.
246 Technical Annual Report 2004-05
Leaf nitrogen % 300 kg/ha 400 kg/ha 500 kg/ha
5.0
4.5
4.0
3.5
3.0 40 DAP 70 DAP 100 DAP 130 DAP 160 DAP 190 DAP
Leaf phosphorus % 120 kg/ha 160 kg/ha 200 kg/ha
0.5
0.4
0.3
0.2 40 DAP 70 DAP 100 DAP 130 DAP 160 DAP 190 DAP
Leaf potassium % 720 kg/ha 960 kg/ha 1200 kg/ha 5.0
4.5
4.0
3.5
3.0 40 DAP 70 DAP 100 DAP 130 DAP 160 DAP 190 DAP
247 Horticulture
Conclusion
This trial showed that the ‘farmer’s rate’ is excessive and that a 40% reduction in fertiliser inputs would result in only a 3-4% reduction in marketable yield. Although the limitations of this trial required that the fertiliser be applied in a solid form, the injection of fertilisers through irrigation would be the method used by growers. The trial will be repeated in 2005 with a demonstration planting using injected fertiliser on the same grower’s property. This will lead to a sound fertiliser recommendation for taro growers in the Top End.
Acknowledgment
• Commercial taro grower Mr. Sok Lee.
• DPIFM Chemistry Laboratory for leaf nutrient analyses.
• DPIFM Biometrician Mark Hearnden.
PROJECT: Evaluating the Use of the SPAD-502 Meter to Manage Nitrogen in Mango Trees (Kensington Pride) in the Northern Territory
Project Officers: A. Gonzalez, G. Azam, T. Maddern and R. Renfree
Location: Darwin and Katherine
Objectives:
To explore the use of the SPAD-502 Minolta chlorophyll meter to assess leaf nitrogen (N) in Kensington Pride (KP) mango trees.
To determine the effect of N applications (urea and KNO3) during the flowering season.
Introduction:
Mangoes (Mangifera indica) are the main horticultural crop in northern Australia. The industry is mainly focused on the main commercial cultivar, KP, which suffers from erratic flowering, excessive vigour and low productivity. Excessive tree growth causes a reduction in flowering activity. Very importantly, excessive N fertilisation is associated with fruit quality issues like green skin on ripe mangoes.
The lack of clear and proven guidelines for N management has encouraged growers to reduce N inputs to avoid fruit quality disorders. Therefore, a tool that would allow growers to estimate leaf N levels in an expeditious way would be advantageous. The chlorophyll meter - Soil Plant Analysis Diagnostic (SPAD) - provides a quick and non-destructive method for estimating leaf chlorophyll content, which is directly related to N status of leaves. The correlation between SPAD values and N status in leaves has not been explored in mangoes.
Method:
Two trials were conducted on growers’ properties during the 2004 mango-growing season. One trial was in Darwin and the other one was in Katherine. A SPAD meter was used to measure the chlorophyll content of leaves. The chlorophyll level was measured as a SPAD unit. The average of SPAD levels was measured by the chlorophyll meter.
248 Technical Annual Report 2004-05
Leaf samples were collected in July 2004, October 2004 and April 2005 from mango trees. On each sampling date and at each location, leaves were collected from the sunny northwest ‘sunny’ side and southeast ‘shaded’ side of the trees for the SPAD readings and tissue analysis. The SPAD level of leaves was measured and groups of leaves with SPAD values within one unit were treated as a single sample.
Individual flushes and leaves within a terminal were monitored for changes in SPAD readings from July to
November 2004. Urea (2%) and KNO3 were applied to trees several times during the trial period. The dynamics of SPAD values during the fruit-growing season were monitored from tagged terminals spread across six groups of trees. The groups consisted of ‘green’ trees which had green leaves; ‘yellow’ trees which had yellowish leaves; ‘shaded side’ trees whose leaves were collected from the south-eastern side; urea treated trees; and KNO3 treated and control trees in Darwin and Katherine. Terminals were randomly selected and tagged. Each terminal had at least three flushes. On each tagged flush, a mature leaf was selected as a reference leaf from which SPAD readings were taken. About five measurements were taken from each flush. The N application included foliar sprays of urea or a solution of KNO3 applied to the soil.
Foliar N
Twenty trees were selected at each site. Ten terminals per tree were selected and tagged. For urea sprays 100 terminals were used. An equivalent number of terminals was sprayed with water and used as a control. A solution of 2% urea was sprayed on selected terminals to run-off level.
Soil N
At each site, 20 trees were selected, 10 of which received soil N and the other 10 were used as a control group (no N). Three terminals per tree were selected and tagged. These terminals were monitored to get the average SPAD levels. The rates of KNO3 were 250 – 300 g/tree/application. In Darwin, 1.75 kg of KNO3 was applied over a period of seven weeks. In Katherine, 1.4 kg of KNO3 was applied over a period of 13 weeks.
Effect of N applications on fruit quality characteristics
All fruit from tagged terminals was collected about a week before harvest and assessed for quality. Fruit quality included dry matter content, weight, total soluble solids and N.
Statistical analysis
The relationship between SPAD values and N concentration was analysed using the GLM procedure of Genstat 6.0. Regression analysis with Groups Routine was used to test similarities in the intercept and slopes of the regression lines. The effect of N applications on fruit size and fruit quality characteristics was analysed using analysis of variance.
Results:
On all sampling dates and in both tree aspects SPAD levels were linearly related to leaf N content (Figure 1), except in samples from the ‘sunny’ side collected in July from the Katherine orchard.
249 Horticulture
1.6 SJ=0.3845+0.0197*X SO=0.2990+0.0197*X DJ DA SA= 0.4495+0.0119*X SJ 1.4 SO
1.2
1.0 DA-SA- DO % N 0.8
0.6
0.4
0.2 10 20 30 40 50 60 SPAD (a)
SJ – Sunny July, SO – Sunny October, DJ – Shaded (Dark) July, DA – Dark April, SA – Sunny April, DO – Dark October.
1.1 DJ = 0.3140+0.0114*X 1.0 SJ = 0.7209-0.0004*X SO DO = 0.4 458 +0. 008 7*X SO = 0.4121+0.0114*X 0.9 DO
0.8 DJ
0.7 SJ
% N 0.6
0.5
0.4
0.3
0.2 10 20 30 40 50 60 SPAD (b)
Figure 1. Relationship between leaf SPAD values and leaf N (%) in mango leaves collected in (a) Darwin and (b) Katherine at different times of the year and from different tree aspects
Effect of N applications on SPAD values
Throughout the time of study, flush SPAD values were highly correlated to SPAD values measured on the reference leaf.
Urea application
The effect of urea applications on SPAD values was analysed on several groups of trees.
‘Green’ trees in Darwin
SPAD values of both treatments started to diverge at about 44 days after treatment. After a few weeks, SPAD values of both control and urea terminals showed a sharp trend to increase (Figure 2 a).
‘Yellow’ trees in Darwin
SPAD values of urea treated terminals increased sharply 44 days after treatment and those of the control remained more or less stable. In both treatments, there was a trend to increase SPAD values at about 60 days after treatment (Figure 2 b).
250 Technical Annual Report 2004-05
‘Green’ trees in Darwin - shaded aspect
The trees responded to foliar urea applications (Figure 2 c).
In Katherine
Trees responded to foliar urea applications. However, there were no statistically significant treatment effects evident (Figure 2 d).
KNO3 application in Darwin and Katherine
Results from these trials indicate that chlorophyll content of leaves did not increase until the second last and last assessment dates in Darwin and Katherine, respectively. There were no statistically significant treatment effects evident in these trials (Figures 2 e and f).
32 50 ad 30 48 28 46 26 44
42 24
40 22
38 20 38 be 38 36
34 36
32 34 SPAD 30 32 28
26 30
50 cf 32 49 30 48
47 28
46 26
45 24 44 1/7 1/8 1/9 1/10 1 /7 1 /8 1 /9 1 /1 0 1 /1 1 DATE DATE
Solid symbols (red), N treated terminals and blank symbols (black), water treated terminals.
Figure 2. Changes in SPAD values observed in leaves of the first flush treated with urea (a, b, c, d) or KNO3 (e, f)
Each graph represents a group of trees: (a) ‘green’ trees in Darwin; (b) ‘yellow’ trees in Darwin; (c) shaded side green trees in Darwin; (d) in Katherine, urea; (e), in Darwin, KNO3 and control trees; (f), in Katherine,
KNO3 and control trees.
Effect of N application on fruit quality characteristics
Fruit characteristics were evaluated for each group of trees which received either urea or KNO3 in Katherine and Darwin orchards. In Darwin, the dry matter content in fruit was significantly higher in the urea treated terminals compared with the water treated terminals (Table 1). The total soluble solid content in fruit was significantly higher in the urea treated terminals compared with the water treated terminals. In Darwin, the N
251 Horticulture content in fruit was significantly higher in the urea treated terminals compared with the water treated terminals (Table 1). Applications of KNO3 or urea as foliar sprays had not significant effect on the fruit size.
Table 1. Fruit characteristics of urea, KNO3 and water treated terminals
Farm Treatment % DM F wt (g) TSS (%) N (%) Katherine Urea 13.5 ±0.9 390 ±107 12.5 ±0.7 0.31 ±0.00 Water 13.2 ±0.6 347 ±63 11.6 ±0.5 0.31 ±0.01 Katherine KNO3 12.6 ±0.8 425 ±106 11.7 ±0.5 0.35 ±0.01 Water 12.9 ±0.6 441 ±73 11.8 ±0.8 0.36 ±0.02 Darwin Urea 13.3 ±0.2 392 ±90 14.3 ±0.5 0.59 ±0.06 Water 12.2 ±0.3 396 ±74 13.2 ±1.4 0.35 ±0.02 Darwin KNO3 12.5 ±0.1 392 ±73 13.7 ±1.5 0.41 ±0.00 Water 13.0 ±0.4 399 ±53 13.9 ±1.2 0.40 ±0.01 Values represent the average and standard deviation (±).
Conclusion:
The SPAD-502 meter could be a useful tool to monitor leaf N levels that will help to increase overall tree health and long-term cumulative fruit yield. Further investigation is warranted.
PROJECT: Effect of Calcium Hydroxide, Surround® and Mangocote® on the Incidence and Severity of Sunburn on Mango Fruit (Kensington Pride) in Katherine
Project Officers: G. Azam, T. Maddern, R. Renfree and C. Newbould
Location: Katherine Region
Objectives:
To evaluate the effectiveness of calcium hydroxide, Surround® and Mangocote® for sunburn protection of mangoes.
To study the use and limitations of calcium hydroxide, Surround® and Mangocote® in Katherine.
Introduction:
Kensington Pride (KP) is the main commercial variety of mango grown in the Northern Territory. Temperatures in Katherine during fruit development from September to October are 170C to 230C at night and 360C to 390C during the day. This causes chlorophyll bleaching or breakdown of exposed fruit. Sunburn causes the surface of fruit to dry and be slightly sunken but firm. The injury can be caused by heating when water or sprayed material on the fruit surface concentrates sunlight or simply when exposed to direct and constant sunlight.
A variety of commercial products such as calcium hydroxide (Ca (OH)2), Surround® and Mangocote® are available to control sunburn. Ca (OH)2, Surround® and Mangocote® provide a dry white film on fruit and foliage, which reflects light and reduces the temperature of fruit. It was therefore expected that Ca (OH)2, Surround® or Mangocote® would reduce the problem of sunburn on mangoes and thus improve fruit quality.
252 Technical Annual Report 2004-05
Method:
Trial sites
Three trials were conducted on KP trees during the 2004 mango-growing season. Two trials were on grower properties and one was at the Horticulture block at Katherine Research Station. Treatments were replicated in four blocks per site. Five sub-samples of fruit were taken from two locations (inner and outer) from each tree, for each treatment. The trial examined coverage, sunburn control and quality of fruit. Repeated measures ANOVA and Pearson Chi-square tests were used to detect treatment effects.
Sites 1 and 2
Each treatment consisted of two single trees per replication and each replication had six trees. The total number of trees in each trial was 24 (3 treatments x 4 replications x 2 trees = 24 trees).
Site 3
Each treatment consisted of four single trees per replication and each replication had eight trees. The total number of trees in the trial was 32 (2 treatments x 4 replications x 4 trees = 32 trees).
Treatments
Applications of Ca (OH)2, Surround® or Mangocote® started on 16 September and finished on 1 November 2004, prior to harvest. The interval between the first two applications was seven to ten days and in subsequent applications it was 10 to 14 days, depending on growth of fruit and weather conditions. Sprays were applied to the point of run-off using a motorised knapsack sprayer. There were five applications in all (Table 3). Tables 1 and 2 show application rates.
Table 1. Treatments for sites 1 and 2
Treatment number Treatment Rate/100 L water 1 Control (no spray) 2 Surround® 5.0 kg 3 Ca(OH)2 5.0 kg
Table 2. Treatments for site 3
Treatment number Treatment Rate/100 L water 1 Control (no spray) 2 Mangocote® 3.0 kg
Table 3. The amount of each chemical sprayed per tree
Treatment Site Quantity/tree (g) Surround® 1 432 Surround® 2 344 Ca(OH)2 1 372 Ca(OH)2 2 341 Mangocote® 3 301
253 Horticulture
Assessments
Spray coverage and fruit sunburn
Within one day of first application, and a day before and after each subsequent application, the proportion of the surface area covered by each product was estimated on each of five inner and five outer fruit per tree. A linear scale based on visual assessment of 1-5 was used, where 1= 0–20%, 2= 20-40%, 3= 40-60%, 4= 60– 80% and 5 =80-100% spray cover or fruit sunburn. Mangoes were harvested on 15, 22 and 25 November at sites 1, 2 and 3, respectively.
Fruit quality
Fruit was weighed and categorised into three grades: A (1st grade), B (2nd grade) and R (reject). Grading specifications are outlined in Table 4.
Table 4. Fruit grading specifications
Grade Description A (1st grade) Yellow bleaching on not more than 20% of surface – no dark or sunken blotches. B (2nd grade) Yellow bleaching on not more than 40% of surface. Discoloured blotches, but not sunken less than 1 sq cm. R (reject) Out of grade.
Results:
Spray coverage
Surround® achieved significantly higher fruit coverage than Ca (OH)2 (Figure 1) in the outer part of fruit. We observed Surround® applied trees had a better white film on foliage and fruit than Ca (OH)2 treated trees. Mangocote® treated trees had a light white film on foliage and fruit.
5.0
4.5
4.0
3.5
3.0
2.5
Percentage of Coverage 2.0
1.5
1.0
Treatment 0.5 Calcium Hydroxide R1: T3 T5 T7 T9 R1: T3 T5 T7 T9 Treatment T2 T4 T6 T8 T10 T2 T4 T6 T8 T10 Surround Location Fruit: Inner Location Fruit: Outer
Figure 1. The mean coverage of fruit achieved with Ca (OH)2 or Surround® at site 1
Fruit sunburn
The incidence and severity of fruit sunburn was significantly lower in the outer part of trees treated with Surround® compared with the control (Figure 2). Mangocote® had no effect on the incidence and severity of sunburn on fruit. It is concluded that Surround® reduced fruit sunburn in the outer part of treated trees compared with control trees.
254 Technical Annual Report 2004-05
1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 Treatment 1.0 Calcium Hydroxide Percentage Sun Percentage 0.9 Treatment 0.8 Control 0.7 R1:T4T5T6T7T8T9T10 R1:T4T5T6T7T8T9T10 Treatment Surround Location Fruit: Inner Location Fruit: Outer
Figure 2. Incidence of fruit sunburn in trees treated with Surround® or Ca (OH)2 at site 1
Fruit quality
There were no significant treatment effects on fruit quality and weight at all sites. At site 1, ‘reject’ fruit numbers were lowest in the Surround® treated trees compared with the other trees. However, the results were not statistically significant. At site 3, ‘A’ grade fruit numbers were higher in the Mangocote® treated trees than in the control trees. However, the results were not statistically different.
PROJECT: Banana Tropical Race 4 Panama Disease Management
Project Officers: M. Darcey, G. Walduck, C. Kelly, A. Daly (Plant Pathology) and S. Smith (Resource Protection)
Location: Coastal Plains Banana Quarantine Station (CPBQS)
Objectives:
To find and develop a commercially acceptable banana variety resistant or tolerant to Panama tropical race 4 for the NT banana industry.
To develop field management methods to reduce the spread of the disease and to extend the commercial life of existing plantations in the NT.
Specifically to:
1. Commission and operate the CPBQS incorporating the CPBQA secure area to conduct secure research on Fusarium oxysporum cubense - tropical race 4 (FOCTR4).
2. Locate and source banana varieties with likely or reputed resistance to FOCTR4 and screen them for resistance or tolerance to FOCTR4 within the CPBQA secure facility.
3. Test the commercial acceptability of any variety found resistant or tolerant to FOCTR4.
4. Develop and commercialise any resistant or tolerant variety found to be commercially acceptable.
5. Develop field management techniques to reduce the spread of the disease and extend the commercial life of existing plantations in the NT.
6. Develop field techniques to disinfest currently infested areas.
7. Assist other research organisations to conduct research on FOCTR4 which may benefit the NT and Australian banana industries.
255 Horticulture
Results:
CPBQS has been successfully operating since 2001 and has passed an external audit every year.
Thirty one banana varieties have been tested or are in the process of being tested.
Four fully resistant varieties have been identified including:
FHIA 25: It is a high yielding tetraploid cooking banana. It is resistant to yellow Sigatoka and was obtained from a breeding program in Central America.
Malaccensis: Three selections of seeded diploids were obtained from Indonesia. They have no commercial value. However, seeds and genetic material are useful for breeding and genetic improvement work.
Highly resistant or tolerant types have been identified:
GCTV119: It is a soma-clonal variant Cavendish which was obtained from a Taiwanese breeding program. It is a very weak plant with small bunches. It is therefore of no commercial value.
FHIA 18: It is a sweet acid dessert type banana which was obtained from a breeding program in Central America. Losses were observed in the plant crop to FOCTR4 but there were few losses in ratoons. It has some commercial potential but has ripening problems. It is resistant to yellow Sigatoka.
FHIA 01: ‘Gold-finger’ is a sweet acid banana which was obtained from a breeding program in Central America. It has commercial potential and was released in Queensland 10 years ago but has post-harvest problems when grown in the tropics.
All other varieties tested so far are susceptible to FOCTR4.
Out of all the varieties tested so far (see Table 1) only three have produced commercial yields and have shown significant resistance to FOCTR4. They are FHIA 01 ’Gold-finger’, FHIA18 and FHIA 25.
FHIA 25 (Figure1) is high yielding and highly resistant to FOCTR4 and yellow Sigatoka. However, it is a cooking type with unacceptably poor taste and texture and a long crop cycle. It is still grown on a small area but all further commercial development work has been suspended until there is some more interest in the market. Spacings of 1450–1550 plants per hectare in a double row configuration with a Cavendish fertiliser program are giving high yields in the trial plots. However, a density of 1450 plants per hectare would probably be most suitable due to the large size of the plants. Small-scale commercial testing this year has indicated that ripe fruit is able to produce acceptable fruit leather (flattened and dried ripe bananas).
FHIA 01(Figure 2) is also known as Gold-finger in Queensland and NSW where it was released a little over 10 years ago. It is a moderately yielding sweet acid type with moderate resistance to FOCTR4 in the plant crop and high resistance in ratoons when grown under high inoculum pressure. It is resistant to yellow Sigatoka and is a robust plant with a vertical bunch producing well-shaped even hands and prata type fingers. Unfortunately, the eating quality is variable when grown under tropical conditions. The pulp does not darken when pealed or cut and is adequate when used in desserts or salads. It may have some potential as a niche banana for local sale. Ripe fruit produces very acceptable dried and leather product. Further small scale testing of a commercial planting is planned to see if there is local interest. Plant density of 1500 - 1600 plants per hectare would appear to be most suitable for NT conditions. From limited data, it appears to cycle some two to four weeks faster than Grand Nain.
FHIA 18 (Figure 3) is a close relative of FHIA01 but is not as robust or as high yielding. It is similar to FHIA01 in that it is only moderately resistant to FOCTR4 in plant crops but highly resistant in ratoon crops. It is 256 Technical Annual Report 2004-05 resistant to yellow Sigatoka .It is currently grown in NSW in very small quantities as a substitute for lady finger.
The plant sun-burns badly and would need some protection if it is to be grown successfully in the NT. This is an issue that can be addressed in commercial production. In ratoons the plant is than FHIA01. It is a sweet acid type with generally acceptable taste but a slight core in the pulp. The semi vertical bunch produces long squarish fingers not as distorted as lady finger. Dropping fingers when the fruit is ripe is a major problem which needs to be overcome before FHIA 18 becomes a fully commercial variety.
Both FHIA 01 and FHIA 18 were almost abandoned after losses of 10-20% to FOCTR4 in the plant crop under high inoculation pressure. Subsequent ratoons have suffered less than 1% losses.
If the plant losses can be reduced by reducing inoculum levels before planting, these two types offer some opportunity to replant FOCTR4-infected patches and produce commercial yields of sweet acid bananas. They are not a substitute for Cavendish.
Figure1. FHIA 25 Figure 2. FHIA 01 Figure 3. FHIA 18
257 Horticulture
Table 1. Summary of characters of varieties being tested against FOCTR4 at CPBQS (HAL project FR00043)
Varieties being tested Type FOCTR4 Susceptible Agronomic Characters/ Market Leaf spot resistance plant cycle ratoon cycles yield production acceptance attributes Cavendish (Williams) AAA VS VS High Good Good No Cavendish (GCTV-119) ex Taiwan AAA SS SS Low Poor Good No FHIA-01 (Gold finger) AAAAB S SS High Very good Variable Yes FHIA-17 AAAA VS VS Variable Good Good Yes FHIA-18 AAAB S S Medium Poor Good Yes FHIA-25 Cooking type R R High Very good Poor Yes SH-3640 (High Noon) AAAB VS VS Good Good Good Some Malaccensis (FOC susceptible) AA S S Very low Good Seeded Yes Malaccensis (FOC susceptible) AA S S Very low Good Seeded Yes Malaccensis (FOC susceptible) AA S S Very low Good Seeded Yes Malaccensis (FOC resistant) AA R R Very low Good Seeded Yes Malaccensis (FOC resistant) AA R R Very low Good Seeded Yes Malaccensis (FOC resistant) AA R R Very low Good Seeded Yes FHIA-23 AAAA VS VS High Poor Average Yes Pissang berungan (Lakatan) AAA EX EX High Good Good No Mutiaria E AAB VS VS Low Good Good Some Novaria D AAA VS VS High Good Good No Novaria G AAA VS VS High Good Good No Pissang embung AA S S Low Good Good No Pissang jari buva AA S S Medium Good Poor (smell) Some Ducasse* AAB S* VS Medium* Good* Good* Some* Cavendish (Grande Nain)* AAA S* S High* Good* Good* No* Improved ladies finger* AAB VS* VS Low* Good* Good* No* Pacific plantain** AAB VS VS High** Good** Cooking** No** Pissang Celon (Mysore)** AAB S Low Good Good No Cavendish (GCTV-Formosana)** AAA S High Very Good Good No D5 (ex South Africa)** AAA VS VS N/A n/a n/a n/a DPM25 (ex South Africa)** AAA VS VS N/A n/a n/a n/a PKZ (ex South Africa)** AAAB? VS VS N/A n/a n/a n/a RSS3 (ex South Africa)** AAA VS VS N/A n/a n/a n/a Parfit ex QDPIF AAA S ? ? Good ? No FOCTR4 susceptibility Agronomic characters EX- Extremely susceptible (dies before emergence) High-medium - commercially acceptable VS – Very susceptible (most develop symptoms and die before harvest) Good-very good – commercially acceptable S – Susceptible (few show symptoms at bunch emergence but many by harvest) SS – Slowly susceptible (few plants show symptoms at harvest) R – Resistant (nil or very rare plant symptoms at harvest)
258 Technical Annual Report 2004-05
Field management procedures developed to contain and slow the disease
Prevention through quarantine
New legislation has been developed in the NT in close collaboration with current growers and the Resource Protection Division to contain and manage the disease. Prevention has been shown to be both practical and feasible in the NT.
Containment of new outbreaks
A number of techniques have been trialled. The burning of the first individual plants as soon as they are detected appears to be the most effective and has been adopted as the preferred treatment. Trials have established that water temperatures above 60°C and for longer than 20 minutes will kill FOCTR4 in plant tissue. These results are the basis of some experimental field control trials currently being established.
Containment and restriction of spread from established infections
The ‘early intervention’ approach where infected plants are detected early and killed by glyphosate injection has reduced the spread rate in existing infected plantings. Its efficacy is attributed to a reduced above ground inoculum.
Prospecting for antagonistic or suppressive organisms from existing FOCTR4 infected sites
This is a joint project between DPIFM and CDU. Currently three Trichoderm isolates capable of parasitising FOCTR4 in laboratory plates have been identified. Samples from existing FOCTR4-infected sites are currently being assessed in the laboratory.
Use of commercially available Trichoderma preparation
A large field trial was established on a commercial planting at risk to FOCTR4. Preliminary results after the first 12 months indicate that the number of plants infected with FOCTR4 is higher in the Trichoderma-treated plots than in the untreated plots. One possible explanation of this is the extra traffic within the Trichoderma plots. The data will be analysed after the second year.
259 Horticulture
Trichoderma Field Trial
30
25
20
Trichoderma 15 Untreated
10 Number of plants showing FOC Symptoms FOC showing of plants Number 5
0 123456789101112131415161718192021222324252627 Fortnightly intervals after planting
Figure 4. Biological suppressants – two Trichoderma isolates from local sources have shown activity against FOCTR4 in laboratory tests
A field trial on a commercial property of a commercial Trichoderma preparation has been commenced and the preliminary results for the first 12 months are shown.
PROJECT: Irrigation Management in Central Australia
Project Officers: A. Nesbitt, D. Salter and I. Broad
Location: Ti Tree/Alice Springs
Objectives:
To validate or modify crop factors used in Central Australia for table grape production
To improve current irrigation practices used in commercial horticulture production in Central Australia
Introduction:
Irrigation scheduling practices on commercial table grape properties in the Ti Tree area vary considerably. Some of these practices can result in under-irrigation or over-irrigation of vines, and can cause a range of problems that eventually affect the economic viability of the planting and the long-term sustainability of the soil.
Excessive applications of water to vines can cause adverse effects in the cropping and fruit quality characteristics of the vine including a high incidence of “chicken” berries, delayed maturity and poor handling and storage characteristics. The extra pumping of water will also add unnecessary costs to production.
260 Technical Annual Report 2004-05
Under-irrigation can also have a detrimental effect to vine growth and productivity. Poor growth, lack of berry-set, failure of the crop to mature (including shrivelling of berries), and nutrition problems, can result if vines do not receive timely and adequate irrigation.
The use of irrigation scheduling aids varies between basic aids such as tensiometers, to more sophisticated state-of-the-art telemetry. Regardless of the sophistication, the main aim of efficient irrigation scheduling is to supply the correct amount of water to a crop at the appropriate time, while maintaining adequate crop and soil health.
The Ti Tree Water Advisory Committee (WAC), a statutory body which represents the interests of water users in the district, has a strong interest in promoting sustainable irrigation practices among users of the resource. WAC has identified project work in the area of crop water use and irrigation scheduling as a priority.
Method:
Over the past 12 months the irrigation project has been active. Data was collected weekly from bore meters, evaporation figures were recorded daily (class A pan) and corresponding crop factors were noted (Table 1) in the Ti Tree Region for analyses. Weekly reports were given to all participating growers in the area. These reports detailed system outputs and compared estimated hours of irrigation needed (based on estimated vine water use) to actual farm use (based on bore meter readings). These reports formed part of an awareness program on farm water use and also provided timely information to WAC on general water use patterns in the area.
Table 1. Crop factors used for table grapes grown in the Pine Hill/Ti Tree area
Month Crop factor (CF) Relevant growth stage January 0.4 February 0.3 Post – harvest March 0.2 Leaf senescence April 0.2 May 0.1 Yellowing/Leaf drop June 0.1 July 0.1 August 0.1 September 0.2 3rd leaf unfolded October 0.5 End flowering/fruit set November 0.55 Veraison/berry softening December 0.4 Full maturity/harvest
This program has allowed the current set of crop factors to be interpreted using vine growth stages. Table 1 shows how the current crop factors can be applied to the different growth stages of the vine. Seasonal variations mean that critical growth stages do not always correspond with the same time in the year. This can actually vary by up to three weeks. Considering that a crop factor is based on the stage of growth of the vine to determine water use, it makes sense to schedule irrigation using a visual estimation of the vine’s growth stage rather than the time of year.
Soil was also monitored throughout the season for relative sodium levels. Soil samples were taken four times throughout the year and analysed for electrical conductivity, pH and exchangeable cations. The exchangeable sodium percentage (ESP) of the soil was calculated and recorded for each farm.
261 Horticulture
Results:
When estimated vine water use is compared with actual farm water use for the past 14 months, the results show a much improved irrigation regime across most farms. Figure 1 shows the average for all farms compared with the estimated vine water use based on evaporation and the corresponding crop factor.
Comparison of water use - All Farms (Average) Weekly readings from 1 May 2004 to 1 July 2005 All Farms (average) Estimated 70 Leaf drop/Dormancy 3rd Leaf End Veraison Maturity/ Post- Leaf senescence Yellowing/leaf drop 65 CF=0.1 CF=0.2 Flowering CF=0.55 Harvest Harvest CF=0.2 CF=0.1 CF=0.5 CF=0.4 CF=0.3 60 55 50 45 40 35 Dormex 30 Application 25 20 15 Water Use (Litres/Vine per Day) 10 5 0
y y n l l p c y n a un ug ov ec ec eb pr pr a Ju J Ju -Ju Oct Jan A A Ju -M 2-Jul 6- 0 A D - -F Mar - -M 7-Ma 4- 8- 1 3 7- 8-Oct 2- 7- 8- 5- 4- 21 1 13-Aug2 10-Se 24-Sep 2 05-Nov19-N 03-De 1 31-D 14-Jan28 11 04-Mar1 01-Apr1 29 13-May27 10-Jun2 Date
Figure 1. Comparison of estimated vine water use to actual farm use for all farms (averaged)
Some issues still exist with under-irrigation throughout the fruit-set and veraison growth stages, as well as some over-irrigation taking place as the vines reach the end of the season. The over-irrigation period can possibly be attributed to some leaching irrigations taking place. Under-irrigation at fruit-set and during berry enlargement stages however, can greatly affect the final quality of the fruit, mainly berry size. This was certainly an area of concern reported by many growers.
Relative salt levels throughout the season show that the current irrigation regimes did not have any detrimental effect on soil health (Table 2). In fact, relative salt levels were lower this season than in previous seasons where over and under-irrigation were more pronounced.
Table 2. Average ESP for the 2004-05 season compared with the December 2003 ESP
Date June 2004 Sept 2004 Dec 2004 Feb 2005 Dec 2003 ESP 6.5 6.9 8.7 7.9 15.1
Creating an increased awareness of irrigation regimes has resulted in improved irrigation practices for the farms involved in the project.
Future work:
As improvements have been achieved in irrigation and related crop factors over the last three years, the program will be scaled down so as to undertake more developmental and extension based activities.
262 Technical Annual Report 2004-05
The new program will include:
• Continued collection and calculation of daily evaporation figures.
• The awareness program will continue to deal with evaporation figures and how to calculate crop water use for individual farms. The information will be circulated weekly (faxed, e-mailed, and may be put on the Web).
• An update on farm water use from bore meter readings will be circulated monthly.
• Water use patterns for the area will be provided to WAC on a quarterly basis.
• An investigation into new moisture monitoring equipment (GBug) will be initiated.
PROJECT: Developing Best Practice Management in Table Grapes in Central Australia
Project Officers: A. Nesbitt, D. Salter, D. King and G. Kenna
Location: Ti Tree
Objective:
To evaluate the performance of various table grape scion/rootstock combinations growing on properties in the Ti Tree area for production of high quality, earl-maturing fruit.
Introduction:
Most plantings in the Ti Tree/Pine Hill area of Central Australia were initially established using own-rooted vine root lings, as the use of rootstocks for nematode resistance was not an issue. Virgin soils in the area were identified as free of those types of nematodes known to cause economic damage to grapevines. The industry also had concerns that the nitrate levels in bore water in the Ti Tree area could lead to management problems and have a detrimental effect on fruit quality due to excess vine vigour. Other positive attributes that rootstocks may have were considered to be of secondary importance to the vigour issue.
As plantings have continued to increase there have been a number of issues that have led to a dramatic change in industry attitudes regarding the use of rootstocks. The pest and disease free status of vine root lings imported into the NT in the past has been questionable. In many instances root lings were found to be infested with root knot nematode (Meloidogyne spp.). This pest (as well as other nematode species) can now be detected in most, if not all, plantings of vines grown throughout the Ti Tree area. Many plantings on properties are now marginal in terms of economic viability due to root knot nematode infestations.
At a joint industry/department rootstock workshop conducted in May 2001, it was agreed that the need to consider the use of rootstocks for table grape production was overdue. Many property owners had already ordered a range of rootstocks grafted to the three main varieties grown in the area: Flame seedless, Menindee seedless and Thompson. The main issue was which rootstocks were best suited to the varieties grown in the area in terms of production of early maturing, high quality table grapes.
263 Horticulture
Desirable characteristics of rootstocks identified for research and evaluation included:
• Nematode tolerance to the range of nematodes which can cause economic damage to table grape plantings.
• Acceptable cropping characteristics including yield, fruit quality and early maturity.
• Compatibility with a range of scion varieties grown in the area.
• Some resistance to termite attack.
• Some salt exclusion characteristics.
• Healthy, vigorous plants.
The sloping T-trellis is the standard trellis system used by all growers in the district. However, recent issues with the cropping characteristics of Menindee seedless and the added vigour imposed by the use of rootstocks have meant that the current trellis system may not be adequate. The industry, in consultation with overseas partners, has been moving toward a more open canopy on large Y- or V- trellis arrangements. While initial studies looked at the benefits provided by the new trellis systems, the lack of large numbers of vines on this trellis made the results difficult to interpret. Therefore, the primary focus of this project was to continue the evaluation of rootstock performance. However, it may take into account the effect of trellis systems when it is clear that they are impacting on vine performance.
Method:
With the assistance of property owners and managers, the various scion/rootstock combinations growing on properties in the area were identified and the vines were tagged. Varieties growing on their own roots were also included in the assessment. The rootstock/scion combinations that are now included in the evaluation program are listed in Table 1.
Table 1. Scion/rootstock combinations under evaluation
Scion Rootstock Scion Rootstock Flame seedless Own roots Thompson Own roots Paulson Schwarzmann Freedom Menindee seedless Paulson Ramsey Ruggeri Paulson Freedom Sultana H5 Schwarzmann Crimson seedless Paulson Harmony Ramsey
Data collection from the plantings includes:
Parameter Indicators Vine vigour Pruning weights Crop load Bud dissections, bunch counts (taken before bunch thinning) Fruit quality Berry diameter, berry weight, Brix and acid measurements Nutrition monitoring Petiole and soil analysis
264 Technical Annual Report 2004-05
Results:
Vine vigour
Pruning weights were taken in previous seasons as a means of assessing vine vigour. Pruning weights completed at this stage show that the average pruning weight for all vines sampled over the past three years was 7.1 kg. In general, Thompson vines had a much lower pruning weight than Menindee seedless vines, with weights of 4.9 kg and 6.8 kg, respectively. Likewise, vines grown on larger trellis systems had larger pruning weights. This does not mean that v-trellis systems impart more vigour, but only that the trellis system allows for a larger vine to be grown in general while maintaining a more open canopy.
As canopy management techniques have become more prevalent, that is, shoot thinning and summer pruning, the use of pruning weights to assess vigour has become antiquated. It is also clear, that for table grape production, vine vigour is secondary to the issues of bud-fruitfulness and fruit quantity and quality. That is, vigour may only be a concern if vines are not producing the yields at the required quality. This may then become an issue of vine balance. In some cases, a more vigorous vine may be desirable and, as mentioned earlier, canopy management techniques, as well as trellis system design, may offset any disadvantages with over-vigorous vines.
Crop loads
Bunch counts have been completed for all scion/rootstock combinations for the past three seasons. Bud dissections were also completed prior to pruning/leaf fall to assess fruitfulness of individual buds. While there was no relationship between fruitfulness and type of rootstock for the bud dissection data, Figure 1 shows that rootstock type may impart some influence on the overall fruitfulness of Menindee seedless when bunch counts were done. The two sets of data may not correlate because of problems with the abortion or death of bunch primordia prior to bud-burst, or that the secondary (less fruitful) buds are bursting on some vines. Further work in this area may be needed.
Bunch numbers were higher for vines grown on Sultana H5, Freedom, Schwarzmann, and Paulsen rootstocks. Sultana H5 however, is the least tolerant to nematodes. Therefore, where nematodes exist, these vines may exhibit poor fruit growth, smaller berries, smaller bunches, and a lack of quality (maturity).
For Thompson vines, there is a trend for Paulson rootstock to perform better. However, the results for the past three years are inconclusive as large variations are seen between years and between different vineyards. At this stage, fruitfulness may have as much to do with management technique as with rootstock selection for Thompson seedless, and to a similar extent for Menindee seedless.
265 Horticulture
Number of bunches for different rootstocks - Menindee seedless
2002 2003 2004 5
4
3
2 Bunches per Cane
1
0 Own H5 Freedom Schwarzmann Paulsen Harmony Ruggeri
Figure 1. Average numbers of bunches per cane for different rootstocks
Quality assessments
Quality assessments were carried out primarily on Thompson and Menindee seedless varieties, on a range of rootstocks. At this stage it is too early to make any conclusions as to the effect of rootstocks on berry quality. However, there are a few trends seen in the current data.
These include:
• A delayed maturity (of up to 10 days) for Menindee/Schwarzmann, when compared with Menindee on own-rooted vines or Menindee/H5.
• An increase in berry size for grafted vines versus own-rooted vines.
While these attributes may appear to be associated with rootstock performance, they may also be a function of cultural management (pruning methods, irrigation regimes, and gibberellic acid applications), the extent of nematode problems and trellis system design.
Nutrition
Six years of continual petiole and soil nutrition monitoring has allowed the development of nutrient standards for the whole season for grapevine cultivars grown at Ti Tree (Appendix 1). These are standards developed for the current list of cultivars sampled over the past six years.
Changes to these standards may occur as information is obtained on the new scion/rootstock combinations, including updated micronutrient standards for vines grafted to Paulson, and Harmony rootstocks. Nutrition programs for Menindee seedless may also need to be looked at more closely in order to promote extra vigour and more fruitful vines.
Conclusion
266 Technical Annual Report 2004-05
Since the nematode problems have become more prevalent in Ti Tree vineyards, evaluating rootstocks for suitability to Central Australia has been a priority for the industry. This program has collected data from the selected trial sites for three continuous years. All of the trial sites have been located on-farm, with growers undertaking normal management practices on each of their respective properties. This was done to ensure the results from these trials were relevant to actual ‘on-farm’ practices. It also means however, that there have been issues with the data because of differences in management between farms.
There is certain evidence to suggest that good management of vines will result in acceptable yields and good quality table grapes regardless of rootstock. The reverse can also be true. The positive attributes of a well suited rootstock can be offset by poor management. However, there are also some trends emerging in the data to date. So far, the data suggests that rootstocks generally perform better than own rooted vines. This is particularly evident when nematodes are present. From all the rootstocks tested, Freedom and Paulsen perform well. Other rootstocks that may show benefits of better fruitfulness are Sultana H5, and Schwarzmann. However, delayed maturity, small berries and bunch size, or hen-and-chicken problems may offset these benefits. Sultana H5, as a V. vinifera variety, has the added disadvantage of being the most susceptible to nematode attack.
It is important to remember that rootstocks are not necessarily resistant to all nematodes, but have varying degrees of tolerance, and may compensate for any nematode damage by imparting extra vigour in the vine. Ramsey may be an exception to this as it does show some resistant characteristics. That means nematodes will affect all vines, depending on the type and level of nematode infestation. The degree to which a vine is affected is also determined by the health of the vine (nutrition, irrigation, soil health) and the type of rootstock.
Information on other rootstocks like Ramsey, Harmony and Teleki is fragmented and difficult to interpret because of low numbers of vines, or incomplete data.
Future work
As it is difficult to interpret the data because of variations between farm management, a new approach to this program may be needed. The current work may continue for one more year in areas that have the potential to deliver outcomes – particularly for Freedom and Paulsen rootstocks. Also, as new vines are planted to replace own-rooted plantings, the opportunity exists to observe new rootstocks and young vine growth.
Through industry consultation, an off-site demonstration block may be established in order to quantify some of the differences we are seeing in the field. The program to date has at least allowed us to gain important knowledge of best practice technologies and techniques that may be applied to such a block. It is hoped that a ‘best practice block’ will be used as a training resource, a repository for the current technology for table grapes in a desert environment and as a trial site for other research activities. This may include management options for nematodes. This is a good opportunity for Government and the industry to work together in a collaborative framework to address critical production issues.
Appendix 1
Tentative petiole nutrient standards for grapevines
Tentative nutrient standards both at flowering (September) and for the October to January period are presented below. The tentative nutrient standards at flowering are those of Robinson et al. (1997), except for the standards used for nitrogen, phosphorus and potassium. These standards were established using the results of the nutrient monitoring program carried out over the past five seasons. The tentative standards will be revised as more information becomes available, and other scion/rootstock combinations are included.
At flowering time (September)
267 Horticulture
Nutrient Adequate range Nitrate nitrogen (mg/kg) 500 - 1200 Total nitrogen (%) 0.8 – 1.0 Phosphorus (%) 0.2 - 0.3 Potassium (%) 2.4 – 3.0 Calcium (%) 1.2 Magnesium (%) >0.4 Sodium (%) >0.5 toxic Chloride (%) >1 – 1.5 toxic Iron (mg/kg) >30 Copper (mg/kg) 6 – 11 Zinc (mg/kg) >26 Manganese (mg/kg) 30 – 60 Boron (mg/kg) 35 - 70
Exceptions to the above standards are indicated below:
• Ramsey or Schwarzmann rootstock vines – phosphorus 0.3 - 0.5%, potassium 3.6 - 4.5%.
• Menindee seedless on own roots – potassium - 3.5 - 4.5 %.
• Menindee seedless – nitrate > 1200 mg/kg (Total N > 1.0 %)
October to January
Nutrient Own roots Rootstocks* Nitrogen (%) 0.5 0.5 Phosphorus (%) 0.2 0.3 Potassium (%) 1.5 – 2.0 2.5 – 3
*The rootstock standards are for vines on Ramsey or Schwarzmann and not for Menindee/H5. For Menindee/H5, the standards are the same as for Thompson vines.
The exception to the above is the potassium standard for Menindee seedless which is 3 – 4%.
October November January Calcium (%) >1.5 >2.0 >2.5 Magnesium (%) >0.5 >0.8 >1.2
The standards for sodium and chloride at flowering are valid for the rest of the season.
268 Technical Annual Report 2004-05
Program: Supply Chain Development
PROJECT: 2004 Mango Crop Forecast Analysis
Project Officer: G. Owens
Location: Berrimah Farm and NTHA Office
Objective:
To analyse the 2004 mango season data against the September, October and November forecasts.
Background:
For the last three years DPIFM Horticulture has published a crop timing forecast for the mango season. This analysis is an evaluation of the accuracy and usefulness of the forecast.
The 2004 October NT mango crop timing forecast successfully predicted the start times, the production pattern for Darwin and Katherine regions and the end of harvest. The earlier forecasts in August and September were less accurate as the August and September average temperatures were much lower than the historical averages used in the heat sum calculations.
This is clearly visible in Figure 1 that shows the Darwin season moving back a full two weeks from the August forecast to the October forecast. The effect was also felt in Katherine but the delay was not as great, as the variation from the normal minimum temperatures was not as much.
Darwin Aug vs Sept vs October Forecast 2004
100
90
80
70
60 Sept
Oct 50 Aug
% Flowering 40
30
20
10
0 38244 38251 38258 38265 38272 38279 38286 38293 38300 38307 38314 38321 38327
Figure1. Mango season forecasting
The forecast was used by growers, packers, labour providers, transporters, wholesalers and retailers to more effectively plan and coordinate this season. The marketing plan was formulated on the basis of the September forecast and consequently the advertising was in full swing before there were significant volumes of fruit in the Sydney and Melbourne markets. 269 Horticulture
In an effort to minimise this in 2005 the heat sums for the crop forecast will be recalculated every fortnight and the forecast republished and distributed. The deadline for most marketing activities is about six weeks prior to the first harvest peak which coincides with about mid September in most years.
The correlation with the October forecast was excellent as seen in Figures 2 and 3.
Darwin Mango flow vs October 1 Prediction 2004
5000 100.0
90.0
4000 80.0
70.0
3000 60.0
50.0
2000 40.0 No ofpallets (@128 trays)
30.0 flowering % from Prediction
1000 20.0
10.0
0 0.0 13-Sep 20-Sep 27-Sep 04-Oct 11-Oct 18-Oct 25-Oct 01-Nov 08-Nov 15-Nov 22-Nov 29-Nov 06-Dec
Katherine Mango Flow vs October 1 Prediction 2004
3000 100.0
90.0
2500 80.0
70.0 2000 60.0
1500 50.0
40.0
1000 No of Pallets @128 trays 30.0 Prediction from % Flowering % from Prediction
20.0 500
10.0
0 0.0 13-Sep 20-Sep 27-Sep 04-Oct 11-Oct 18-Oct 25-Oct 01-Nov 08-Nov 15-Nov 22-Nov 29-Nov 06-Dec
Figures 2 and 3. Darwin and Katherine mango flow charts
The Horticulture Division wishes to thank all the growers and packers that contributed to the forecast through the flowering surveys and the contribution of mango flow figures during the season. It is due to wide industry participation that the forecast becomes more accurate each year. We look forward to working with even more growers next year.
270 Technical Annual Report 2004-05
PROJECT: Vapour Heat Treatment Project
Project Officer: G. Owens
Location: VHT treatment plant, Jabiru Tropical Orchards, Berry Springs
Objective:
To facilitate access to the new vapour heat treatment (VHT) plant at Jabiru orchards by other Top End mango growers for export to Japan and to assist in developing quality assessment guidelines for selecting fruit for treatment and export.
Background:
VHT is required for fruit fly disinfestation for export of Australian KP mangoes to Japan and now China. It will be required by other countries in the near future. A new private VHT plant has been built at Berry Springs by Jabiru Tropical Orchards to develop an export business in mangoes to Japan and other countries requiring VHT of mangoes for fruit fly eradication.
Fruit suitable for VHT must be internally and externally sound to stand the process. Fruit for export to the Japanese market must be of high class 1 standard and have adequate blush.
The objective of this project was to facilitate other NT mangoes growers to trial their fruit through VHT and the quality assessment process to become eligible for the export market to Japan and elsewhere.
Eleven mango growers from across the Darwin and Katherine growing areas volunteered to trial their mangoes through the treatment process. The sizes of the consignments varied from small trial samples to repeat commercial quantities. The quality of the fruit was assessed at the selection stage, and after treatment. There was a wide range of quality outcomes, even from the same supplier.
Multiple pathways for the fruit to get from the trees to the treatment facility were identified with good and poor outturns for most systems. The common factor underlying good outcomes of any pathway was the care with which the fruit was handled. Quality feedback reports highlighted individual grower’s quality issues.
VHT accelerates the ripening process of mangoes and accentuates blemishes, bruising and any skin damage. Unsuitable fruit is quickly exposed and the defects are readily categorised. Some suitable fruit was identified, treated and exported along with that of the VHT operator. Other lines were repackaged for the domestic second grade market. Some growers will need to improve their quality performance to be acceptable suppliers to this facility and to the export markets.
Mature fruit from early in the season has a better record of performance through VHT with the later fruit maturing faster and becoming too ripe for treatment. Growers need to commit fruit from the start of their season to maximise their chances of a good outturn with VHT.
Growers who took part in the trial now have a clearer concept of what is required to proceed down this path to export mangoes using VHT.
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Program: Horticulture Information Service
PROJECT: Horticulture Information Service
Project Officers: G. Owens, A. Black, J. Thomas, G. McMahon, J. Bird and A. Nesbitt
Location: Berrimah Farm, KRS and AZRI
Objective:
To develop, package and efficiently deliver information for industry development.
Background:
The Horticulture Division has a long history of supplying information and information products to its many and varied client groups. The demand for information and the need for an up to date, consistent and accountable information service have led the Horticulture Division to invest resources to form a dedicated Horticulture Information Service team.
Results:
The service provided displays and horticulture information products to NT Information Centres in Darwin, Katherine, Tennant Creek and Alice Springs, the “Go for 2 fruit & 5 vegetable” campaign, NTAgA and NTHA shopfronts, DPIFM offices, retail nurseries and farm suppliers in Darwin, Katherine and Alice Springs, Taminmin Community Library and many schools.
Farms database was created, information was updated and checked for horticultural producers within Connect:NT to enhance efficiency and improve client information handling.
The service was enhanced with the publication of three new Fact Sheets, eight Growing Notes, two Product Description Language charts, eight Recipe and Preparation Sheets and 12 miscellaneous publications; compilation of 24 new “Information Packages” and attendance at eight promotional events.
The horticulture website was continually developed with all new publications, direct access to past research projects, seasonal information for growers, a large number of useful links and up-to-date general information.
The Extension Officer (Information) supported the Connect:NT client management system throughout the Horticulture Division, including the Katherine and Alice Springs regions and assisted in its implementation across other Primary Industries at Berrimah Farm.
272 Technical Annual Report 2004-05
Horticulture Information Service Total Number of Requests 2004/05 Total Number of Hits on Web Site
70 700 651 60 600
50 500 474 439 40 400 368 349 327 30 300 HitsWebSite on
Total Numberof Requests 20 200
10 100
0 0 July September November January March May 2004 Requests 2005 Requests Hits on Web Site
Figure 1. Number of requests through Connect:NT and hits on the Horticulture website
273 Primary Industries
PUBLICATIONS, CONFERENCE PAPERS AND PRESENTATIONS
Scientific Journal/Proceeding Publications
Azam, M. G. N., Walter, D. E., Waite, G. K. and Hargreaves, J. R. (2005). Rainforest habitat resistance to the migration of Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) in south-eastern Queensland. Australian Journal of Entomology 44, 52-56.
Daly, A., Hennessy, C. and Schultz, G. (2005). New host record for the grapevine leaf rust fungus, Phakopsora euvitis. Australasian Plant Pathology (in press).
Hennessy, C., Walduck, G., Daly, A. and Padovan, A. (2005). Weed hosts of Fusarium oxysporum f. sp. cubense, tropical race 4 in northern Australia. Australasian Plant Pathology 34(1): 115-117.
Schmidt, S. and Brown, G. (2005). A new genus and species of Australian pergid sawfly (Hymenoptera: Symphyta, Pergidae) causing damage on grass (Poaceae). Zootaxa 955: 1–8 (2005).
Smith, E.S.C. and Chin, D. (2004). Grower adoption of integrated pest management systems in tree crops in northern Australia. In: 22nd International Congress of Entomology, Brisbane, 15-21 August.
Streten, C., Conde, B., Herrington, M., Moulden, J. and Gibb, K. (2005). Candidatus Phytoplasma australiense is associated with pumpkin yellow leaf curl disease in Queensland, Western Australia and the Northern Territory. Australasian Plant Pathology 34(1):103–105.
Other publications/Presentations
Bhuiyan, S. (2004). Alternaria leaf spot, a sticky problem for North Australian cotton. Katherine Rural Review, No. 259.
Bhuiyan, S. (2005). Katherine plant pathology lab wants your sick plants and fruits. Katherine Times, 13 April.
Bhuiyan, S. (2005). Study of alternaria leaf spot on cotton in Northern Australia. Final Annual Report 2004- 05, Australian Cotton CRC, May.
Bhuiyan, S. (2004). Biological warfare against sorghum ergot. Australasian Plant Pathology Society meeting, Darwin, November.
Bhuiyan, S. (2004). Alternaria and other diseases of cotton in Katherine and Kununurra. Cotton research review and planning meeting, Darwin, November.
Bhuiyan, S. (2005). Alternaria leaf-spot of cotton in Katherine and Kununurra. FUSCOM PLUS, Cotton pathology meeting, Narrabri, June.
Bhuiyan, S. (2004). The mango sea-freight project. Mango sea-freight group meetings, Katherine/Kununurra, September.
Bhuiyan, S. (2005). Local best practice, Plant Pathology. Local best practice group meeting, Katherine and Mataranka, July.
Bhuiyan, S. (2005). Diseases that may occur in winter vegetables. Article for a school plot manual.
274 Technical Annual Report 2004-05
Brown, H. (2004). Presentation on insects and preservation of specimens. Anula Primary School, November.
Chin, D. (2005). Mango leafhopper in backyards and orchards. Territory Times, June.
Chin, D. (2005). Pests that affect fruit quality. Presentation to Wepack growers, June.
Chin, D. (2004). Flatids: those little suckers on mangoes. Litchfield Times. 01 December.
Chin, D. (2004). Red-banded thrips and crusader bugs appear in orchards and rural blocks, Litchfield Times. 04 August.
Chin, D. (2005). Mango leafhopper in backyards and orchards. Territory Times. June.
Chin, D., McMahon, G. and Brown, H. (2004). Workshop to rambutan growers on the use of new resources: Integrated pest management manual, poster and monitoring software, October.
Chin, D., Churchill, T., Brown, G. R. and Webber, J. (2004). Common spiders in the Darwin area. DPIFM Agnote No. I63.
Condé, B., Arao-Arao, I. and Pitkethley, R. (2004). Screening snake bean and cowpea varieties and lines for resistance to snake bean Fusarium wilt. Australasian Plant Pathology Society meeting, November.
Connelly, M., Broughton, S. and Krajewski, A. (2004). Citrus integrated pest management workshop, Katherine Research Station, July.
Daly, A. (2005). Grapevine leaf rust. Bugmatch Grapes ®V 3.0 CD-ROM (CRC for Viticulture and Aventis).
Diczbalis, Y. and McMahon, G. (2004). Minor tropical fruits. In: The New Crop Industries Handbook. RIRDC Canberra.
Entomology Section, (2005). Mango leafhopper (poster). Second edition, June.
Entomology Section, (2005). Diversity of insects and mites and their damage to plants – static and interactive display. Fred’s Pass Rural Show, May.
Entomology Section, (2005). Mouthparts of insects and mites (poster), May.
Entomology Section. (2005). Insect and mite damage on plants (poster) Second edition, April.
Hoskins, M. (2004). What is biological farming all about? Katherine Rural Review, September.
Hoskins, M. (2004). Mango pests. Mango special feature, rural pages, Katherine Times, 15 September.
McMahon, G. and Wicks, C. 2004. Effect of rootstock on rambutan tree size and yield in the Northern Territory. Poster presented at the 6th National Lychee Conference incorporating the 1st Australian Sapindaceae Crop Conference, Cairns, September.
Smith, E.S.C. (2004). Possible ACIAR projects in crop protection that could involve DBIRD as the Australian commissioned agency and various agencies in Papua New Guinea. ACIAR Report, October.
Smith, E.S.C. (2005). European house borer incursion in Western Australia. Australian Environmental Pest Managers Association. Darwin, April.
Smith, E.S.C. (2005). Fruit fly management in Vietnam. Provincial People’s Committee, Loong Luong Commune, Moc Chau, Son La Province, Vietnam, June.
275 Primary Industries
Smith, E.S.C., Pitkethley, R. N., Thistleton, B. M., Conde, B. D. and Chin, D. (2004). Assessment of the risk of entry of nominated plant pests and diseases to the Katherine Region. Katherine Horticultural Advisory Forum, July.
Thistleton, B. M. (2004). Control of giant termites, Mastotermes darwiniensis in tree crops in the NT. DPIFM Cashew Workshop, August.
Thistleton, B. M. (2004). Presentation on termites. The NT Minerals Council, October.
Thistleton, B. M. (2005). Starting to design a survey: Steps 1 to 6 of guidelines for plant pest surveillance in the Pacific. Workshop on enhanced surveillance for plant pests. Pak Chong, Nakhon Ratchasima, Thailand, June.
Thistleton, B.M. (2005). More about surveys to support pest free area status. Workshop on enhanced surveillance for plant pests. Pak Chong, Nakhon Ratchasima, Thailand, June.
Thistleton, B.M. and Neal, M. (2005). Giant termite Mastotermes darwiniensis in the Northern Territory. Environmental Pest Managers Association. Darwin, April.
Thistleton, B. M., Wallace, H. and Neal, M. (2005). Progress Report on research trials of Conogethes pluto in Alpinia, to NTHA cut-flower group, June.
Thistleton, B.M., Smith, E.S.C. and Neal, M. (2005). Cryptotermes dudleyi in a Darwin house. Environmental Pest Managers Association, Darwin, April.
Walduck, G. and Daly, A. (2005). A brief history of Fusarium wilt tropical race 4 of bananas in the NT and its control. Australian Banana Conference, Cairns, June.
West, S. J. (2005). National Grapevine Leaf Rust Eradication Program Progress Report. The National Vine Health Steering Committee, Adelaide, May.
West, S. J. and Black, D. M. (2004). Grapevine leaf rust national eradication program. 12th Australian Wine Industry Technical Conference, Melbourne, July.
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