Integrated Pest Management of Major Pests affecting Sweetpotato, Ipomoea batatas, in the Caribbean
D. Michael Jackson, Janice R. Bohac (USDA-ARS, US Vegetable Laboratory); Kathy M. Dalip, Lilory McComie, Llewellyn Rhode (Caribbean Agricultural Research Development Institute [CARDI]); Phillip Chung, (Rural Agricultural Development Authority [RADA]); Dak Seal (University of Florida); Dionne Clarke-Harris, Francis Aseidu, Frank D McDonald, (CARDI)
Abstract Year X as they were plagued by problems of drought and loss through grazing by Several dry-flesh sweetpotato breeding lines and livestock. varieties were evaluated at Charleston in South Carolina, Homestead in Florida, Basseterre in St. Kitts and Bodles in Jamaica, for resistance to soil Objectives insect pests, including sweetpotato weevils, sweetpotato leaf beetles, flea beetles, and the WDS • Evaluate the potential of resistant varieties, (Wireworm-Diabrotica-Systena) complex. Several biorationals (insect growth regulators, new entries with insect resistance and desirable entomopathogenic nematodes, fungi and agronomic characteristics were indicated from field bacteria) and botanical insecticides for data from the United States. Breeding lines were managing sweetpotato weevils and grubs of selected based on adequate yields, desirable skin and the sweetpotato leaf beetle. flesh colors, and overall resistance/tolerance to the • Evaluate the performance of USDA- insect pests. Once again, PI531116, Picadito, Sidges developed, red-skinned, cream-fleshed and Fire-on-Land were among those entries with the sweetpotato clones and local (Jamaican and greatest insect pest resistance. Tinian (a new entry), OECS) export sweetpotato lines under though not a prolific producer, also showed high Caribbean growing conditions. resistance to the insect pests and should be included • Working with participatory groups to in further trials. disseminate sweetpotato weevil IPM technology An adult bioassay was developed for evaluating • Regionalize sweetpotato weevil IPM sweetpotato germplasm for resistance to spotted technology within selected countries in the cucumber beetles (Diabrotica undecimpunctata Caribbean through demonstration and howardi Barber) and banded cucumber beetles (D. training. balteata LeConte). Five proprietary kairomone lures were evaluated for trapping spotted and banded cucumber beetles in sweetpotato fields. Traps were IPM Constraints Addressed quite effective for monitoring spotted cucumber
beetles, but they were less effective for monitoring Sweetpotato weevils, sweetpotato leaf beetles, and banded cucumber beetles. the WDS soil insect complex significantly reduce
sweetpotato production in Jamaica and the rest of Ten types of pheromone traps were evaluated for the Caribbean. The incorporation of pest monitoring sweetpotato weevils (Cylas formicarius management tactics, such as cultivating resistant elegantulus [Summers]) during 2001 and 2002. A breeding lines, implementing cultural practices and modification of Talekar’s trap proved most effective, using environmentally friendly insecticides such as but traps constructed from 5-gallon pails or milk botanicals and biorationals, into the present IPM jugs also captured significant numbers of weevils. technology will greatly assist IPM procedures for These trap designs are being tested in the Caribbean. sweetpotato farmers in the Caribbean to produce
high quality, internationally competitive commodity. The regionalisation component of the sweetpotato Additionally, the dissemination of IPM technology IPM, initiated in Year 6 under the project, to farmers in major sweetpotato-growing areas in the continued. However, this year’s activities were Caribbean is continuing and should facilitate the limited to St Kitts and Nevis where varietal trials goal of reducing pest damage and improving and on-farm demonstrations were conducted. sweetpotato production in the Region such that it is However, the varietal trials have to be repeated in competitive in the global market.
Research Methods, Results and Impacts Yield: The yield of the sweetpotato entries ranged between 1.09 to 10.96 Kg/plot and 18 to 82 roots/ (1) Evaluation of yield and insect resistance traits of select plot, with several entries producing significantly USDA cream-flesh sweetpotato clones and standard higher yields than others (Table 1). The highest Jamaican sweetpotato clones mean mass of tubers was obtained from TIS 30-30, Sixteen mostly dry-fleshed sweetpotato cultivars, breeding PI 531116 (from the breeding programme of the lines, and plant introductions were evaluated at the Bodles International Institute for Tropical Agriculture in Research Station, St. Catherine, Jamaica in 2001-2002. The Nigeria) and Picadito, while Tinian produced the trial, which was established in August 2001, consisted of 25- lowest mean total mass (1.09 Kg/replication). The plant plots of each breeding line planted on beds 23 - 30 cm sweetpotato entry 96-86 produced a significantly high, 1m wide and spaced at 30-cm intervals. Treatments higher mean number of roots (81.6 roots/replication) (breeding lines) were allocated in a randomized complete block than any other entry, followed by 94-127 (81.6 design with four replicates. roots/replication). Sidges and Tinian produced the least (19.0 and 18.0 roots/replication, respectively) number of roots. It is not surprising that Tinian did Yield and Horticultural Traits. The tubers were harvested five not produce many roots as it is a fine-stemmed plant months after planting and graded into three size categories and took a while to become established after it was relating to local and export market standards (culls, marketable planted from cuttings sent by Drs Bohac and I and II). The number of roots within each category was Jackson from the US Vegetable Laboratory. counted and weighed (kg). Observations on shape, skin and
flesh color were recorded. Insect Resistance: The WDS index among the
entries ranged from 0.12 to 2.56, and 4 entries had Insect Resistance. Roots were scored for pest damage resulting WDS ratings significantly lower than the check from sweetpotato leaf beetle larvae, sweetpotato weevils, white cultivar SC 1149-19 (Table 1). Tinian produced the grubs, Wireworm-Diabrotica-Systena complex (WDS) and flea highest percentage of roots with no insect damage beetles. For 1sweetpotato weevils and 2sweetpotato leaf beetle (% clean, Table 1), while Fire-on-Land produced the larvae, damage was scored on a scale of 0 - 5 and 0 - 4 based lowest (9.3). This is in contrast to previous trials in on percentage surface and internal damage and length of which the latter entry was among those that feeding channels, respectively. Roots damaged by 3WDS were produced the highest percentage of clean roots. This rated by assigning each root a score based on the number of result may have been because the trial had to be re- feeding scars. Flea beetle damage was calculated as a established in the same field and the fast-growing proportion of total root damage. For each pest scored, a Fire-on-Land produced tubers earlier than some of severity damage index was calculated using the formula below. the other varieties hence giving pests more time to
do their damage. Severity Index Formula
(a x Score 0) + ...... + (a x Score 5) Both crowns and roots were rated for damage by Total Number of Roots sweetpotato weevils (Table 1), and PI 531116 (Root where a = number of roots with the particular score and Crown Indices = 0.14 and 0.49, respectively)
from the breeding program of the International Statistical Analysis. Data were analysed by Analysis of Institute for Tropical Agriculture in Nigeria was the Variance (ANOVA) using Genstat for Windows (2nd Ed.) most resistant to this pest. Other entries which statistical software. showed tolerance were Picadito (Root and Crown Indices = 0.32 and 2.66, respectively), Sidges (Root Research Results and Discussion and Crown Indices = 0.40 and 1.19, respectively), Fire-on-Land (Root and Crown Indices = 0.93 and 1.24, respectively) and Tinian (Root and Crown 1 Sweetpotato Weevil, Cylas formicarius Damage Rating. Crown - 0= no injury, Indices = 0.64 and 1.31, respectively. This is in 1= 1- 20% injured tissue, 2= 21- 40%, 3= 41- 60%, 4= 61- 80%, 5= 81- 100%.. accordance with results from previous trials. The Root - 0= no injury, 1= larval tunnels 0.01 - 0.50 cm deep and 0 - 6% internal tissue injury, 2= larval tunnels 0.5 - .0 cm deep and 6 - 12% internal tissue injury, susceptible lines, Beauregard and SC1149-19, 3= larval tunnels 1.0 - 1.5 cm deep and 12 - 24% internal tissue injury, 4= larval showed low tolerance to the weevil (Root Indices = tunnels 1.5 - 2 cm deep and 24 - 48% internal tissue injury, 5= larval tunnels 0.2.18 and 1.44, and Crown Indices = 4.43 and 4.32, greater than 2 cm deep and >48% internal tissue injury. respectively), with only one other entry, TIS 80/637
2 Immatures of the Sweetpotato Leaf Beetle, Typophorus viridicyaneus sp. gouge (Root Index = 2.97), that was more susceptible. shallow areas on the surface of sweetpotato roots. Damage rating based on the length of feeding channels. 0= no injury, 1= >0 - 8 cm channel, 2= >8 - 15.0 cm Several sweetpotato entries, such as 94-127, PI channel, 3= >15 - 23cm channel, 4= >23 cm channel. 531116, White Regal, Sidges, Tinian and TIS 30-30,
3 Wireworm-Diabrotca-Systena complex (WDS) Score based on the number of showed resistance to sweetpotato leaf beetle larvae feeding scars (0= no scars, 1= 1- 5 scars, 2= 6 - 10 scars, 4= more than 10 (Table 1). scars). Flea Beetle Damage - Narrow grooves just below surface
differ significantly according to analysis of variance, Once again, PI531116, Picadito, Sidges and Fire-on-Land were probably due to very low insect populations. among those entries with the greatest insect pest resistance. Tinian (a new entry), though not a prolific producer, also Impact showed high resistance to the insect pests and should be The development of new insect-resistant, dry-flesh included in further trials. sweetpotato varieties with good yield and quality has the potential to improve sweetpotato production Impact in Jamaica and other Caribbean nations. The The use of pest resistant plant varieties is one strategy that is identification of those varieties that have proven to often employed in IPM programmes. The identification of US be tolerant to the insect pest complex in Jamaica and and Jamaican sweetpotato breeding lines that are relatively the Caribbean is one step in the process of high pest-tolerant, is one step in the development of a practical quality sweetpotato production in the Region. sweetpotato IPM programme to reduce infestation by, and hence, crop loss due to different sweetpotato pests. The (3)Evaluation of plastic traps baited with a floral inclusion of such pest-tolerant sweetpotato breeding lines into lure in the monitoring of cucumber beetle the present IPM programme can be an economical approach to (Diabrotica spp.) populations in sweetpotato plots managing certain sweetpotato pests that can then be transferred in the USA to other countries in the Caribbean, which have similar island ecosystems. Research Methods For the third year, floral-lure baited plastic traps (2) Evaluation of yield, quality and insect resistance traits (proprietary design from Trécé Corporation) were of USDA sweetpotato cultivars in the USA placed in sweetpotato plots in North Carolina, South Carolina (two locations), and Louisiana to monitor Research Methods cucumber beetle (Diabrotica spp., a component of At Charleston, South Carolina and Homestead, Florida, 68 and the WDS complex) populations in the fields. 46 mostly dry-fleshed, sweetpotato cultivars, breeding lines, and plant introductions were evaluated in 2001-2002. The Research Results and Discussion sweetpotato plants were evaluated for yield, quality, and insect Both spotted cucumber beetle, Diabrotica resistance in three experiments at Charleston and two undecimpunctata, and banded cucumber beetle, D. experiments at Homestead. balteata, were captured in the traps. The traps in North Carolina and the inland areas of South Research Results and Discussion Carolina captured only D. undecimpunctata. Both of these species contribute to WDS damage in Charleston, South Carolina sweetpotatoes. This trapping system was very The WDS indices among these 68 entries were lower than in efficient for monitoring spotted cucumber beetles, years past and ranged from 0.00 to 1.16 (Tables 2 - 4). In the but not banded cucumber beetles during 2000-2001 first two field tests, 46 entries had WDS ratings significantly (Figures 1 & 2). lower than the susceptible check cultivars ‘Beauregard’ and SC 1149-19 (Tables 2 and 3), indicating high levels of resistance to Impact the insect pest complex throughout this germplasm base. The development of new insect monitoring Significant levels of resistance to white grubs and flea beetles techniques for sweetpotato pests such as cucumber were also observed. However, sweetpotato weevil population beetles will serve to increase the variety of tactics levels were too low to provide conclusive results (Tables 2 - 4). that can be incorporated in an effective IPM programme for sweetpotato, which can be extended Homestead, Florida to other countries in the Region. The WDS indices among the 46 entries ranged from 0.05 to 1.90, and 41 entries had WDS ratings significantly lower than (4) Evaluation of the efficacy of different the check cultivars ‘Beauregard’ and SC 1149-19 (Tables 5 and sweetpotato weevil pheromone trap designs in the 6). Unfortunately, sweetpotato weevils and grub ratings monitoring of sweetpotato weevil populations (probably Typophorus nigritus viridicyaneus [Crotch]) did not
Table 1. Insect ratings and weights of dry-fleshed sweetpotato entries and check cultivars in four replications at Bodles, St. Catherine, Jamaica, 2001-2002
Sweetpotato Sweetpotato Total Weight6 Sweetpotato Entry WDS Index1 % Clean Roots2 Weevil4 Crown Sweetpotato Leaf5 Number of Roots7 Weevil3 Index (Kg) Rating Beetle Index Quarter Million 0.12 c8 12.2 e-h8 0.75 b-d8 3.17 b8 2.32 b8 4.03 cd8 30.5 e-g8 TIS 8401 0.12 c 19.3 d-h 0.54 cd 3.01 b 1.05 b-d 3.34 cd 36.3 d-g 94-127 0.13 c 41.4 a-c 1.84 a-c 2.14c 0.41 d 2.43 cd 72.3 ab PI 531116 0.13 c 30.8 a-e 0.14 d 0.49 e 0.87 b-d 10.34 a 53.3 b-d TIS 30-30 0.21 bc 24.9 b-f 0.68 cd 3.01 b 0.93 b-d 10.96 a 65.3 a-c Fire-On-Land 0.26 bc 9.3 e-h 0.93 b-d 1.24 d 1.72 b-d 7.21 b 35.3 d-g Sidges 0.35 bc 34.7 a-d 0.40 d 1.19 d 0.87 b-d 5.00 bc 19.0 g Tinian 0.37 bc 51.0 a 0.64 cd 1.31 d 0.89 b-d 1.09 d 18.0 g White Regal 0.40 bc 22.0 c-g 0.88 b-d 2.58 bc 0.71 cd 2.76 cd 45.3 c-e TIS 2498 0.41 bc 0.8 h 0.76 b-d 3.13 b 1.50 b-d 3.52 cd 30.0 e-g 96-86 0.44 bc 14.2 d-h 1.05 b-d 2.93 b 1.06 b-d 4.01 cd 81.6 a Picadito 0.49 bc 13.4 e-h 0.32 d 2.66 bc 1.61 b-d 10.43 a 53.0 b-d Beauregard 0.79 bc 0.0 h 2.18 ab 4.43 a 2.00 bc 2.06 cd 23.2 fg W-341 1.02 bc 7.8 f-h 0.89 b-d 2.07 c 1.24 b-d 4.43 bc 43.5 d-f SC 1149-19 1.17 b 2.0 gh 1.44 b-d 4.32 a 1.34 b-d 3.19 cd 51.3 cd TIS 80/637 2.56 a 45.8 ab 2.97 a 2.96 b 3.96 a 2.18 cd 28.3 e-g
1WDS (Wireworm-Diabrotica-Systena) rating index computed as: (A + 2B + 4C)/N, where A = number of roots scored 1-5 feeding scars, B = number of roots scored 6-10 feeding scars, C = number of roots scored >10 feeding scars, and N = total number of roots scored. Numbers are averages from four replications. 2Roots showing no visible damage from insect pests 3Cylas formicarius elegantulus (Summers). Roots rated 0= no injury, 1= larval tunnels 0.01 - 0.50 cm deep and 0 - 6% internal tissue injury, 2= larval tunnels 0.5 - .0 cm deep and 6 - 12% internal tissue injury, 3= larval tunnels 1.0 - 1.5 cm deep and 12 - 24% internal tissue injury, 4= larval tunnels 1.5 - 2 cm deep and 24 - 48% internal tissue injury, 5= larval tunnels greater than 2 cm deep and >48% internal tissue injury 4Cylas formicarius elegantulus (Summers). Crowns subjectively rated 0= no injury, 1= 1- 20% injured tissue, 2= 21- 40%, 3= 41- 60%, 4= 61- 80%, 5= 81- 100% 5Immatures of sweetpotato leaf beetle, Typophorus nigritus viridicyaneus (Crotch) gouge shallows areas on the surface of sweetpotato roots. Damage rating based on the length of feeding channels. 0= no injury, 1= >0 - 8 cm channel, 2= >8 - 15.0 cm channel, 3= >15 - 23cm channel, 4= >23 cm channel 6Average total weight for each replication. 7Average number of roots for each replication. 8Means separated Fisher’s Least Significant Difference after Analysis of Variance (SAS Institute. 1989. SAS/STAT User’s Guide, Version 6, Fourth Edition, Volumes 1 & 2. SAS Institute, Inc., Cary, N.C., 1674 pp.). ns = Non-significant treatment effects in ANOVA
Research Methods Research Results and Discussion A new sweetpotato weevil trap constructed from a five- As was observed in a previous trial, the modifications of gallon bucket, which was observed by Dr. Jackson and traps described by Proshold et al. (1986) and Talekar (1988) others while visiting a grower’s field in Antigua in captured the most sweetpotato weevils in 2001 and 2002 November 2000, was compared with six other pheromone- (Figures 3 and 4). baited traps for their efficacy in trapping adult weevils. The traps included (i) modification of Talekar’s trap described in The five-gallon bucket trap was also very effective in 2001, Talekar, N. S. 1988. How to control sweetpotato weevil: a but not thus far in 2002. The Universal trap and Sticky trap practical IPM approach. AVRDC Publ. 88-292, Taiwan, worked quite well in 2002. Interestingly, the milk jug trap, R.O.C., 6 pp., (ii) modification of Proshold et al.’s (1986) which is commonly recommended for use in the Caribbean funnel trap in Proshold, F. I., J. L. Gonzalez, C. Asencio, (Lawrence and Myers, 1999) was less effective in South and R. R. Heath. 1986. A trap for monitoring the Carolina. Pheromone traps are quite effective in monitoring sweetpotato weevil (Coleoptera: Curculionidae) using populations of sweetpotato weevils (Figure 5). It should be pheromone or live females as bait. J. Econ. Entomol. noted that these traps will continue to be monitored for an 79:641-647, (iii) Universal trap, (iv) milk jug trap described additional 100 days or so during the 2002 season to by Lawrence and Myers in Lawrence, J. and P. Meyers. complete the comparison with the numbers caught in 2001 1999. Construction and Use of Pheromone Traps in (Figure 5). Sweetpotato Production. Factsheet, Caribbean Agricultural Information Service (CAIS), 4 pp., (v) Japanese beetle trap, Impact and (vi) plastic Trécé Diabrotica trap, were monitored at Continued improvement in the design of sweetpotato weevil Charleston, SC during 2001. pheromone traps, particularly the homemade types made of recyclable containers, will enhance the effectiveness of the In 2002, the two least effective traps (Japanese beetle trap existing IPM technology in reducing the weevil populations and Trécé Diabrotica trap) were omitted from the study, and in the field and hence, the damage by this pest to harvestable three additional trap designs (Pherocon sticky trap, boll roots. weevil trap, and Multipher trap) were added to the experiment.
Table 2. Average insect ratings and weights of 29 dry-fleshed sweetpotato entries and check cultivars in four replications at Charleston, SC, 2001
Sweetpotato WDS Index1 % Clean Roots2 % of Roots with3 % of Roots with4 % of Roots with5 Total Weight6 Number of Roots7 Entry Flea Beetle Damage Grub Damage Sweetpotato Weevil (Kg) Damage
94-145 0.14 h8 86.8 a8 1.2 e8 0.0 ns8 0.0 c8 0.95 e8 51.7 a-f8 95-161 0.11 h 73.6 a-c 8.2 de 12.6 0.0 c 1.97 a-e 44.0 a-f 94-127 0.15 gh 78.4 ab 6.4 de 4.4 0.5 c 1.70 b-e 58.0 a-e W-325 0.15 gh 68.2 a-f 8.7 c-e 11.2 6.1 c 1.86 a-e 52.3 a-f 97-88 0.17 f-g 71.7 a-d 14.0 c-e 7.6 1.0 c 0.68 e 36.7 a-f 96-86 0.19 e-h 73.1 a-c 8.7 c-e 2.8 1.1 c 1.25 c-e 45.3 a-f W-341 0.20 e-h 63.5 a-g 14.7 c-e 9.9 3.9 c 1.17 c-e 41.7 a-f Sumor 0.21 e-h 61.9a-g 18.4 a-e 7.5 2.2 c 2.77 a-e 63.3 a-e W-326 0.22 e-h 58.3 a-h 12.7 c-e 17.7 1.4 c 1.10 c-e 34.7 b-f W-332 0.25 d-h 68.2 a-f 17.6 b-e 1.3 0.0 c 1.86 a-e 28.0 ef 97-22 0.27 d-h 61.1 a-h 7.8 de 11.9 1.7 c 1.06 de 32.3 c-f 98-294 0.27 d-h 53.6 b-h 17.5 b-e 15.8 0.5 c 3.41 a-c 67.7 a-d 97-95 0.29 d-h 69.0 a-e 8.3 c-e 2.5 0.9 c 3.30 a-d 71.7 ab 95-102 0.30 d-h 47.4 c-h 22.4 a-e 22.1 1.8 c 2.65 a-e 46.0 a-f White Regal 0.32 d-h 53.9 b-h 9.5 c-e 7.5 3.6 c 2.42 a-e 69.3 a-c 95-175 0.32 d-h 45.1 c-h 24.4 a-e 22.7 2.3 c 4.05 a 73.7 a 97-72 0.35 d-h 54.6 b-h 11.9 c-e 13.1 3.2 c 1.74 a-e 58.7 a-e 96-47 0.36 d-h 59.7 a-h 9.7 c-e 11.3 0.5 c 2.16 a-e 53.7 a-f 95-233 0.36 d-h 56.1 b-h 13.9 c-e 9.0 2.6 c 2.35 a-e 63.3 a-e 97-94 0.37 d-h 56.7 b-h 4.9 de 2.4 0.0 c 0.80 e 29.0 d-f 97-81 0.39 c-g 34.7 g-j 22.6 a-e 18.3 5.9 c 2.35 a-e 50.0 a-f W-345 0.43 b-g 40.1 e-i 32.9 a-c 13.6 10.3 c 1.25 c-e 26.0 ef Picadito 0.45 b-f 40.0 e-I 26.6 a-d 18.0 6.1 c 1.78 a-e 26.3 ef 97-92 0.46 b-f 31.2 h-j 41.7 a 9.7 5.4 c 2.08 a-e 40.7 a-f SC 1149-19 0.47 b-e 11.3 j 40.0 ab 21.6 36.7 a 3.60 ab 62.3 a-e W-364 0.52 b-d 46.0 c-h 9.8 c-e 9.8 6.5 c 4.03 a 62.0 a-e GA 90-16 0.66 a-c 42.0 d-h 11.1 c-e 33.7 8.4 c 1.17 c-e 16.3 f Beauregard 0.67 ab 38.1 f-j 15.2 c-e 15.1 11.6 bc 2.54 a-e 57.0 a-e W-315 0.77 a 13.1 ij 40.2 ab 11.9 21.7 b 2.16 a-e 28.3 ef 1WDS (Wireworm-Diabrotica-Systena) rating index was computed as: (A + 2B + 4C)/N, where A = number of roots scored A (1-5 feeding scars), B = number of roots scored B (6-10 feeding scars), C = number of roots scored C (>10 feeding scars), and N is the total number of roots scored. Numbers are averages from four replications. 2Roots showing no visible damage from insect pests. 3Sweetpotato flea beetle, Chaetocnema confines Crotch. 4White grubs, primarily Plectris aliena Chapin. 5Cylas formicarius elegantulus (Summers). 6Average total weight for each replication. 7Average number of roots for each replication. 8Means separated by Fisher’s Least Significant Difference after Analysis of Variance (SAS Institute. 1989. SAS/STAT User’s Guide, Version 6, Fourth Edition, Volumes 1 & 2. SAS Institute, Inc., Cary, N.C., 1674 pp.). ns = Non-significant treatment effects in ANOVA.
Table 3. Average insect ratings and weights of 33 dry-fleshed sweetpotato entries and check cultivars in four replications at Charleston, SC, 2001 % of Roots with3 % of Roots with4 % of Roots with5 Total Weight6 Sweetpotato Entry WDS Index1 % Clean Roots2 Number of Roots7 Flea Beetle Damage Grub Damage Sweetpotato Weevil Damage (Kg) Camote Blanco Franja 0.12 f8 78.0 a8 3.1 ns8 10.8 c-e8 0.0 ns8 0.63 hi8 21.5 e-l8 IAC-72 Eucaru 0.16 e-f 57.6 a-e 4.1 25.2 a-e 0.0 0.76 hi 14.7 g-l NZ-196-(613) 0.18 e-f 60.9 a-d 6.7 21.2 a-e 0.0 0.27 hi 10.3 h-l TIS 70357 0.18 e-f 58.0 a-e 8.3 20.4 a-e 1.9 1.19 g-i 17.3 f-l Tanzania 0.18 e-f 52.0 a-f 20.8 20.7 a-e 4.2 0.71 hi 14.8 g-l CN-1028-15 0.20 d-f 72.9 ab 27.2 0.0 e 0.0 0.28 hi 6.0 kl Jonathan 0.21 d-f 58.7 a-e 6.3 23.0 a-e 0.0 0.77 hi 12.8 g-l Lam 52 0.21 d-f 46.6 a-f 19.9 27.4 a-e 0.0 0.57 hi 16.0 f-l Tapato 0.25 d-f 55.5 a-f 16.2 22.5 a-e 0.0 1.42 e-i 16.5 f-l TIS 80/637 0.25 d-f 52.3 a-f 8.6 21.3 a-e 0.0 1.62 d-h 25.8 d-j Tinian 0.25 d-f 50.0 a-f 50.0 0.0 e 0.0 0.11 i 2.5 l Lam 66 0.26 d-f 70.7 a-c 6.3 22.0 a-e 0.0 0.28 hi 9.3 j-l Sumor 0.26 d-f 52.8 a-f 27.2 17.3 a-e 0.0 3.58 bc 45.0 bc Camote Blanco 623 0.29 d-f 7.0 b-f 25.2 17.4 a-e 1.4 0.65 hi 14.5 g-l Lam 102 0.30 d-f 55.8 a-f 12.7 11.7 c-e 0.0 1.25 f-i 27.8 c-j Chino A 0.32 d-f 56.6 a-e 14.1 14.5 b-e 0.8 3.38 bc 34.0 b-f Minamiyutaka 0.32 d-f 40.6 a-f 21.5 27.7 a-e 1.6 2.61 b-f 28.5 c-i Cuba 2 0.33 d-f 48.8 a-f 11.9 3.6 ed 0.0 0.31 hi 6.3 kl TIS 8401 0.33 d-f 46.3 a-f 26.4 23.1 a-e 0.0 0.45 hi 8.8 j-l White Regal 0.34 d-f 66.4 a-d 4.3 9.0 de 0.0 3.13 bc 43.8 bcd TIS 2525 0.36 d-f 48.2 a-f 6.3 6.7 de 0.0 0.31 hi 9.5 i-l Picadito 0.37 d-f 38.6 a-f 17.3 43.4 a 0.0 2.87 b-e 24.5 e-k IB 05 0.41 c-f 44.4 a-f 11.1 18.5 a-e 0.0 0.68 hi 27.0 d-j Camote Amarillo 0.45 c-f 7.6 b-f 9.0 41.4 ab 0.0 0.80 hi 11.0 h-l TIS 9101 0.46 c-f 29.7 d-f 20.8 28.3 a-e 3.0 3.86 b 64.0 a Hernandez 0.49 b-f 36.5 b-f 11.0 37.5 a-c 0.7 2.30 c-g 29.0 c-h TIS 3053 0.53 b-e 36.7 b-f 27.5 19.2 a-e 0.0 1.42 f-i 15.0 g-l TIB 8 0.57 b-d 38.4 a-f 10.3 14.8 a-e 4.8 1.59 d-i 21.7 e-k Jewel 0.59 b-d 27.5 d-f 25.1 30.6 a-d 2.2 3.49 bc 37.8 b-e G 1990 0.74 bc 31.3 c-f 14.6 21.8 a-e 2.0 7.8 a 48.3 b Beauregard 0.84 b 20.6 ef 16.2 24.1 a-e 4.4 2.93 b-d 27.8c-j SC1149-19 1.16 a 16.2 f 15.3 20.1 a-e 2.1 2.95 b-d 31.8 b-g 1WDS (Wireworm-Diabrotica-Systena) rating index was computed as: (A + 2B + 4C)/N, where A = number of roots scored A (1-5 feeding scars), B = number of roots scored B (6-10 feeding scars), C = number of roots scored C (>10 feeding scars), and N is the total number of roots scored. Numbers are averages from four replications. 2Roots showing no visible damage from insect pests. 3Sweetpotato flea beetle, Chaetocnema confines Crotch. 4White grubs, primarily Plectris aliena Chapin. 5Cylas formicarius elegantulus (Summers). 6Average total weight for each replication. 7Average number of roots for each replication. 8Means separated by Fisher’s Least Significant Difference after Analysis of Variance (SAS Institute. 1989. SAS/STAT User’s Guide, Version 6, Fourth Edition, Volumes 1 & 2. SAS Institute, Inc., Cary, N.C., 1674 pp.). ns = Non-significant treatment effects in ANOVA.
Table 4. Average insect ratings and weights of 14 dry-fleshed sweetpotato entries and check cultivars in four replications at Charleston, SC, 2001
% of Roots with5 % of Roots with3 % of Roots with4 Total Weight6 Sweetpotato Entry WDS Index1 % Clean Roots2 Sweetpotato Weevil Number of Roots7 Flea Beetle Damage Grub Damage (Kg) Damage
Picadito 0.00 b8 100.0 a8 0.0 ns8 0.0 ns8 0.0 ns8 0.17 d8 6.0 e8 97-21 0.13 ab 61.4 bc 5.2 16.3 11.8 1.29 bc 53.7 ab
Sumor 0.15 ab 79.6 ab 2.2 3.3 0.0 1.29 bc 43.3 a-c
W-344 0.20 ab 67.5 b 7.4 6.9 3.3 0.83 b-d 20.3 de
97-19 0.21 a 63.0 bc 5.7 11.8 1.3 0.87 b-d 23.0 c-e
GA90-16 0.23 a 75.8 ab 2.1 7.9 0.0 0.38 d 20.0 de
Simone 0.23 a 38.8 cd 2.2 30.8 12.8 0.87 b-d 17.3 de
White Regal 0.24 a 68.6 b 0.0 5.1 5.1 0.87 b-d 38.7 a-d
95-188 0.28 a 66.9 bc 2.6 4.2 2.3 0.68 cd 19.7 de
94-207 0.28 a 57.5 bc 8.4 19.0 0.0 0.42 d 22.3 de
95-10 0.29 a 57.6 bc 8.1 8.1 3.2 1.44 ab 35.3 cd
97-56 0.30 a 58.1 bc 5,4 14.1 5.2 0.80 b-d 20.7 de
W-305 0.30 a 30.2 d 10.5 40.1 11.8 2.05 a 56.0 a
94-140 0.31 a 58.6 bc 14.2 4.4 2.9 1.14 bc 31.7 cd
1WDS (Wireworm-Diabrotica-Systena) rating index was computed as: (A + 2B + 4C)/N, where A = number of roots scored A (1-5 feeding scars), B = number of roots scored B (6-10 feeding scars), C = number of roots scored C (>10 feeding scars), and N is the total number of roots scored. Numbers are averages from four replications. 2Roots showing no visible damage from insect pests. 3Sweetpotato flea beetle, Chaetocnema confines Crotch. 4White grubs, primarily Plectris aliena Chapin. 5Cylas formicarius elegantulus (Summers). 6Average total weight for each replication. 7Average number of roots for each replication. 8Means separated by Fisher’s Least Significant Difference after Analysis of Variance (SAS Institute. 1989. SAS/STAT User’s Guide, Version 6, Fourth Edition, Volumes 1 & 2. SAS Institute, Inc., Cary, N.C., 1674 pp.). ns = Non-significant treatment effects in ANOVA.
Table 5. Average insect ratings and weights of 30 dry-fleshed sweetpotato entries and check cultivars in four replications at Homestead, Florida, 2001-2002.
% of Roots with % of Roots with Total Weight5 Sweetpotato Entry WDS Index1 % Clean Roots2 Sweetpotato Weevil Grub Damage3 (Kg) Damage4
95-161 0.08 i6 92.5 a6 0.0 ns6 0.0 ns6 1.76 f-l Patriot 0.10 i 82.5 ab 7.5 0.0 1.04 I-l 95-102 0.15 g-i 82.2 ab 5.3 0.0 0.93 j-l Ruddy 0.15 g-i 82.5 ab 2.5 0.0 5.31 bc 97-95 0.18 g-i 62.5 b-e 20.0 0.0 4.10 b-d Sumor 0.23 f-i 67.5 a-e 10.0 0.0 3.46 c-g 96-47 0.23 f-i 77.5 a-c 0.0 0.0 1.46 g-l 97-22 0.27 f-i 63.3 b-e 6.7 0.0 1.80 e-l 97-94 0.38 f-i 70.0 a-d 12.5 0.0 3.38 c-g W-326 0.31 f-i 69.4 a-d 5.0 0.0 1.53 g-l 94-127 0.33 e-i 60.0 b-e 7.5 0.0 2.91 d-j 95-233 0.35 e-i 72.5 a-d 2.5 0.0 1.54 g-l 94-145 0.35 e-i 72.5 a-d 0.0 0.0 2.55 d-l 96-86 0.38 e-i 72.5 a-d 0.0 0.0 1.23 h-l W-332 0.59 d-i 55.0 b-f 8.3 0.0 3.67 c-f Simone 0.53 c-i 40.0 e-j 7.5 2.5 9.22 a 97-82 0.53 c-i 60.0 b-e 17.5 0.0 3.85 b-e W-341 0.55 c-i 47.5 d-h 10.0 0.0 3.64 c-f W-345 0.58 c-i 52.4 c-g 10.8 0.0 0.50 l White Regal 0.63 c-i 47.5 d-h 7.5 0.0 2.24 d-l 97-72 0.68 c-h 45.0 d-i 15.0 0.0 2.31 d-l 97-88 0.73 c-g 39.2 e-j 12.5 20.0 1.21 h-l 97-92 0.78 c-f 45.0 d-i 15.0 0.0 2.16 d-l 97-81 0.91 c-e 39.0 f-j 17.9 0.0 2.93 d-j Picadito 1.00 cd 25.0 g-j 7.5 0.0 5.61 b 96-51 1.03 b-d 17.5 ij 7.5 20.0 0.73 kl W-364 1.04 b-d 21.3 h-j 0.0 0.0 3.03 d-I 95-175 1.10 bc 15.0 j 15.0 0.0 4.20 b-d Minimiyutaka 1.60 ab 22.5 h-j 12.5 2.5 3.18 d-h Beauregard 1.90 a 12.5 j 12.5 5.0 2.79 d-k
1WDS (Wireworm-Diabrotica-Systena) rating index was computed as: (A + 2B + 4C)/N, where A = number of roots scored A (1-5 feeding scars), B = number of roots scored B (6-10 feeding scars), C = number of roots scored C (>10 feeding scars), and N is the total number of roots scored. Numbers are averages from four replications. 2Roots showing no visible damage from insect pests. 3 Primarily the sweetpotato leaf beetle, Typophorus nigritus viridicyaneus (Crotch). 3Cylas formicarius elegantulus (Summers). 5Average total weight for each replication. 6 Means separated by Fisher’s Least Significant Difference after Analysis of Variance (SAS Institute. 1989. SAS/STAT User’s Guide, Version 6, Fourth Edition, Volumes 1 & 2. SAS Institute, Inc., Cary, N.C., 1674 pp.). ns = Non-significant treatment effects in ANOVA.
Table 6. Average insect ratings and weights of 17 dry-fleshed sweetpotato entries and check cultivars in four replications at Homestead, Florida, 2001-2002
% of Roots with4 % of Roots with3 Total Weight5 Sweetpotato Entry WDS Index1 % Clean Roots2 Sweetpotato Weevil SPLB Damage (Kg) Damage Lam 66 0.05 e6 95.0 a6 0.0 ns6 0.0 ns6 4.01 c-g6
NZ 196 0.07 e 90.0 ab 0.0 0.0 0.64 g
Sumor 0.13 de 87.5 ab 0.0 0.0 3.32 e-g
TIS 3053 0.15 de 85.0 ab 0.0 0.0 9.09 a
IAC-72 0.23 de 75.0 a-c 0.0 2.5 3.14 e-g
Chino A 0.28 de 65.0 a-e 0.0 10.0 3.32 e-g
TIS 70/357 0.31 c-e 74.4 a-d 0.0 0.0 1.27 g
TIS 8401 0.33 c-e 70.0 a-e 0.0 0.0 6.73 a-d
Camote Amarillo 0.33 c-e 47.5 c-e 0.0 7.5 5.73 b-e
Tinian 0.33 c-e 66.7 a-e 0.0 0.0 2.41 fg
Picadito 0.38 b-e 62.5 b-e 2.5 0.0 7.05 a-c
White Regal 0.45 b-e 62.5 b-e 0.0 0.0 3.36 e-g
Camote BlancoFranja 0.48 b-e 59.2 b-e 0.0 0.0 2.95 e-g
TIS 80637 0.70a-d 67.5 a-e 0.0 0.0 3.86 c-g
TIS 9101 0.90 a-c 47.5 c-e 0.0 0.0 4.68 b-f
Tapato 0.98 ab 42.5 de 0.0 5.0 7.27 ab
Beauregard 1.15 a 40.0 e 2.5 0.0 3.77 d-g
1WDS (Wireworm-Diabrotica-Systena) rating index was computed as: (A + 2B + 4C)/N, where A = number of roots scored A (1-5 feeding scars), B = number of roots scored B (6-10 feeding scars), C = number of roots scored C (>10 feeding scars), and N is the total number of roots scored. Numbers are averages from four replications. 2Roots showing no visible damage from insect pests. 3 Primarily the sweetpotato leaf beetle, Typophorus nigritus viridicyaneus (Crotch). 4Cylas formicarius elegantulus (Summers). 5Average total weight for each replication. 6Means separated by Fisher’s Least Significant Difference after Analysis of Variance (SAS Institute. 1989. SAS/STAT User’s Guide, Version 6, Fourth Edition, Volumes 1 & 2. SAS Institute, Inc., Cary, N.C., 1674 pp.). ns = Non-significant treatment effects in ANOVA.
0.8 Spotted Cucumber Beetles Banded Cucumber Beetles
0.6
0.4
0.2 Number of Beetles/Trap/Night of Number
0.0 160 180 200 220 240 260 280 300 320 Day of the Year
Figure 1. Average number of adult cucumber beetles (Diabrotica spp.) captured per day with five types of proprietary kairomones in two sweetpotato fields at the US Vegetable Laboratory, Charleston, SC, in 2000
3.0 Spotted Cucumber Beetles Banded Cucumber Beetles 2.5
2.0
1.5
1.0
Number of Beetles/Trap/Night of Number 0.5
0.0 160 180 200 220 240 260 280 300 320 340 360 380 400 Day of the Year
Figure 2. Average number of adult cucumber beetles (Diabrotica spp.) captured per day with five types of proprietary kairomones in two sweetpotato fields at the US Vegetable Laboratory, Charleston, SC, in 2001
1200 Modified Talekar Trap (1988) Funnel Trap (Proshold et al. 1986) Five-Gallon Plastic Pail Trap Yellow & White Universal Trap (Great Lakes IPM) 1000 Milk Jug Trap (Lawrence and Myers 1999) Plastic Trécé Diabrotica Trap Japanese Beetle Trap (Great Lakes IPM) 800
600
400
C umulative N umber200 of Adult Weevils
0 160 180 201 222 243 264 285 306 330 Day of the Year
Figure 3. Cumulative number of sweetpotato weevils (Cylas formicarius elegantulus [Summers]) captured by seven types of traps at the US Vegetable Laboratory, Charleston, SC, in 2001
500 Modified Talekar Trap (1988) Funnel Trap (Proshold et al. 1986) Pherocon Sticky Trap (Trécé Inc.) Yellow & White Universal Trap (Great Lakes IPM) 400 Bio Contrôle Services Multipher Trap Milk Jug Trap (Lawrence and Myers 1999) Five-Gallon Plastic Pail Trap Boll Weevil Trap (Great Lakes IPM)
300
200 C umulative Adult Weevils 100
0 150 175 200 225 250 Day of the Year
Figure 4. Cumulative number of sweetpotato weevils (Cylas formicarius elegantulus [Summers]) captured by eight types of traps at the US Vegetable Laboratory, Charleston, SC, in 2001
5) Development of a bioassay to measure the resistance of sweetpotato weevil from time to time. The farmers were sweetpotato germplasm to cucumber beetles (Diabrotica introduced to the use of pheromone trapping (using local spp.) materials) to complement cultural control and reduced dependence on use of pesticides to control the sweetpotato Research Methods weevil C. formicarius. On one farm, the homemade traps A laboratory bioassay was developed at the US Vegetable were first placed in one field when the crop was about two Laboratory, Charleston, South Carolina, for evaluating months old, while they were placed in a second field when feeding damage by adult cucumber beetles on storage roots the crop was about five weeks old. Both fields were from 17 sweetpotato genotypes. A single adult cucumber harvested at the same time, when the traps had been in the beetle was placed on a small piece of root with periderm and first field for six weeks and four weeks in the second. cortex with the stele removed. This piece of sweetpotato skin was embedded in plaster and enclosed in a Petri dish so Research Results and Discussion that the beetle was forced to feed through the periderm. In field I, weekly weevil counts for the six-week period Pieces of sweetpotato skin were changed as needed, and ranged between 94 and 1,912 (Total of 3,596 weevils adult longevity was measured captured in six weeks) while in field II, they were between 230 and 5,441 (total of 9,479 weevils captured in four Statistical Analysis. Data were subjected to Fisher’s Least weeks). An assessment of the crop loss from the two fields Significant Means Test after Analysis of Variance using is given in Table 7. The high weevil population did not SAS Institute (1989) statistical software. adversely affect the roots as root damage due to weevil was very low in field I and non-existent in field II. This was due Research Results and Discussion to the fact that the farmer planted the vines deep and molded For both banded and spotted cucumber beetles, adults on the beds often, in addition to the presence of the traps, which several insect-resistant sweetpotato genotypes had caught high numbers of weevils, especially in field II, which significantly shorter live spans than those that fed on the was planted later than field I. susceptible controls (Figures 6 and 7). It was observed that adults which were starved did not live significantly longer Impact than those that were fed on several sweetpotato entries, Efficient and effective insect bioassays are crucial for including Sumor, 96-86 and Tinian, indicating resistance of accelerating the development of pest-resistant sweetpotato these entries, which is confirmed by the WDS indices germplasm. obtained in field varietal trials carried out at Charleston and Homestead (Tables 2 – 6). Conversely, beetles that survived (7) Dissemination of IPM technology to sweetpotato the longest included the susceptible checks SC1149-19 and farmers and extension officers Beauregard, as well as W-341, Simone and Jewel. Again, this serves to confirm results obtained in the varietal trials JAMAICA (Tables 2 – 6). CARDI Jamaica, in collaboration with the Rural Agricultural Development Authority, RADA, hosted a one- Impact day workshop on the Integrated Management of sweetpotato Efficient and effective insect bioassays are crucial for pests, with emphasis on the sweetpotato weevil (SPW), accelerating the development of pest-resistant sweetpotato Cylas formicarius L., in January 2002, in Santa Cruz, St germplasm. Elizabeth. The workshop was sponsored by CARDI/USAID IPM CRSP, RADA and Agricultural Support Services (6) Regionalization of sweetpotato IPM technology Project (ASSP) and attended by extension officers of RADA within the Caribbean region St Elizabeth. In his introduction, Phillip Chung, Senior Plant Protection Specialist, RADA and National Coordinator ST KITTS CIPMNET, gave a general overview of IPM principles and On-farm transfer of IPM technology for management of urged the participants to take keen note of the information the sweetpotato weevil with sex pheromone trapping as a they were to receive as the SPW was a serious pest in main component Jamaica and was causing significant losses to sweetpotato farmers in the region. Dionne Clarke-Harris, Entomologist Research Method and IPM CRSP Site Coordinator and Kathy M Dalip, In Year 8, a comparison of crop losses done on a Entomologist and Project Manager, made presentations on sweetpotato farm before and after sweetpotato IPM the IPM CRSP activities in Jamaica and the Caribbean and technology was introduced showed that the farmer was able IPM of sweetpotato, respectively (Plate 1). Anthony to reduce crop loss to sweetpotato weevil from 31.1% to Trought, Research Assistant on the sweetpotato project, 7.7% one year after applying IPM recommendations. At the showed the participants how to recognise and assess the end of Year 8 and the beginning of Year 9, work began with damage done by the different pests. other farmers whose sweetpotato fields were attacked by the
4000 2001
3500 2002
3000
2500
2000
1500
1000
Cumulative Number of Weevils of Number Cumulative 500
0 150 200 250 300 350 Day of the Year
Figure 5. Cumulative number of sweetpotato weevils (Cylas formicarius elegantulus [Summers]) captured by all ten types of traps at the US Vegetable Laboratory, Charleston, SC, during 2001 and 2002
200.0 a 180.0
160.0 b 140.0
120.0
100.0
80.0
Longevity in Days c 60.0 cd
40.0 cde cde cde cde de de 20.0 de de e e e e e e e e 0.0
l et al 7 e 6 n d O -19 63 nch ia 274 -341 one -244 eg 1 -364 6-8 Di Stele 49 -H2 W- W im Jewel W R W W-28 Bu Exc Sumor 9 Tin tarve ial uregard S S d 11 a ific 9-19 PI 399 ina rt 4 SC Be ol arve A St C 11 Car S
Figure 6. Average longevity of adult banded cucumber beetles (Diabrotica balteata) fed periderm and cortex of 16 sweetpotato entries, 2001-2002 (Means separated by Fisher’s Least Significant Difference after Analysis of Variance)
180.0
160.0 a a 140.0
120.0
100.0
b 80.0 b bc bcd
Longevity in Days in Longevity 60.0 bcde bcdef 40.0 cdefg defg cdefg efg efg efg fg g 20.0 g g g g g
0.0
9 d l h ga 86 an 61 9-1 -364 -341 -274 ni -1 rve d l Diet egar Re Jewel 96- Excel a r W Bunc W-244 W W W-287 Sumor Ti 95 114 Simone St icia -19 Stele na if li PI 399163 rt 49 SC Beau A Starved-H2O Caro SC 11
Figure 7. Average longevity of adult banded cucumber beetles (Diabrotica balteata) fed periderm and cortex of 17 sweetpotato entries 2001-2002 (Means separated by Fisher’s Least Significant Difference after Analysis of Variance
Table 7: Comparison of on-farm crop losses on one farm in St Kitts Production of sweetpotato in Parameter Field I Field II Total mass % of total Total mass % of total (Kg) harvested (Kg) harvested Total harvest 13.5 21.50 Total damaged 3.25 24.07 8.20 38.14 Sweetpotato weevil damage 0.20 1.48 0.00 0.00 White grub damage 0.10 0.74 0.400 1.86 Rat damage 0.10 0.74 0.400 1.86 Immature 0.75 5.56 3.70 17.21 Cracking 3.00 22.22 2.20 10.23 Marketable 7.25 53.7 11.10 51.63
Plate 1. Sweetpotato IPM being presented by Dr KM Dalip (standing)
Plate 2. Mrs Yvonne Grindley, Zonal Plant Protection Specialist, RADA (sixth from left) demonstrates how to make the SPW pheromone traps from recycled plastic containers to the participants
The afternoon practical session took place in a sweetpotato DM Jackson attended the National Sweetpotato farmer’s field, where Yvonne Grindley, Zonal Plant Collaborators Meeting, 2 – 3 February, 2002, Kissimmee, Protection Specialist, RADA, showed the participants how Florida. to make the SPW pheromone traps from recycled plastic DM Jackson and J Bohac served as members of the containers, after which they practised making their own and Sweetpotato Crop Germplasm Committee. placed them in the field (Plate 2). The factors affecting B. Research Investigator Exchanges. placement of the traps were pointed out to them. DM Jackson traveled to Jamaica 17-23 February, 2002 to assist in harvest of sweetpotatoes and to plan for future ST KITTS & NEVIS cooperative work. CARDI St Kitts Nevis participated in the Annual Open Day DM Jackson met with Aziz Lagnaoui (CIP, Lima, Peru) in hosted by the Department of Agriculture, St Kitts at La Lima to discuss cooperative work with Beauveria bassiana. Guerite in April 2002 and Nevis in May 2002. The Open DM Jackson and KM Dalip met with cooperators at IPM Days were held to showcase agricultural products and CRSP Technical Committee Meeting. services provided by the agricultural community in the country. CARDI’s display featured sweetpotato under the Research Information and product exchange. theme “ Sweet Potato – From the Field to the Factory “. The display was in three parts. The first part consisted of Assistance given to collaborating scientists with research mounted specimens and photographs of 10 local and 14 equipment, supplies and/or other support: USDA - supplied sweetpotato cultivars. Part 2 concentrated DM Jackson shipped proprietary (Trécé) lures and traps to on the management of the sweetpotato weevil and comprised cooperators in Jamaica. posters, CARDI/IPM CRSP factsheets, and pheromone- JR Bohac and DM Jackson shipped USDA-developed, dry baited traps and specimens of the weevil, while Part 3 fleshed sweetpotato clones to Kathy Dalip to evaluate their displayed food items made from sweetpotato such as chips, potential in Jamaica. spicy bread, biscuits, cheesecake and pudding, prepared by DM Jackson presented seminar “Overview of staff members in collaboration with the local school meals Pest-Resistance/Sweetpotato Breeding Program” at CARDI, programme. In addition, a number of packaged products University of the West Indies, Kingston, Jamaica, 21 sourced from the USA were also displayed, including February, 2002 sweetpotato chips supplied by DM Jackson. Biscuit, scone and pancake mixes were sourced privately by Llewellyn Rhodes, the CARDI Representative. Samples of the food Publications and Presentations items were offered to visitors, which included hundreds of school children, housewives, Government Ministers and Variety Releases officials. The response was extremely favourable with the Bohac, J. R., P. D. Dukes, Sr., J. D. Mueller, H. F. Harrison, overwhelming comment being surprise at the diverse and J. K. Peterson, J. M. Schalk, D. M. Jackson, and J. novel products that could be prepared from sweetpotato. Lawrence. 2001. ‘White Regal’, a multiple pest- and disease-resistant, cream-fleshed, sweetpotato. HortScience Handouts on sweetpotato production and recipes for selected 36:1152-1154. items were distributed. An evaluation questionnaire was Kays, S. J., W. J. McLaurin, Y. Wang, P. D. Dukes, J. R. fielded to 30 visitors to evaluate their impressions of the Bohac, and D. M. Jackson. 2001. GA90-16: A nonsweet, sweetpotato products. Based on the response and interests staple-type sweetpotato breeding line. HortScience. 36:175- generated from the open day, activities for Year 10 sought to 177. include the exploration of different varieties in the development of value-added products and the publication of Abstracts and Reports a compilation of sweetpotato recipes taken from the Region. Bohac, J. R., J. K. Peterson, D. M. Jackson, H. F. Harrison, and M. E. Snook. 2001. Increased efficiency of selection of pest resistant sweetpotato breeding lines through Networking Activities identification and quantitation of biochemical resistance Workshops and Scientific Meetings. compounds. Abstract AIII-O-1 in Guide for Participants, S Tolin, D Clarke-Harris, K M Dalip, S Fleischer, C Sweetpotato: Food and Health for the Future, an Edwards and D M Jackson, together with J Momson and C international symposium sponsored by the International Harris, participated in the IPM CRSP Technical Meeting and Society for Horticultural Science (ISHA), the International Annual Planning Workshop, Blacksburg Virginia, in 15-18 Potato Center (CIP), and the Universidad Nacional Agraria May 2002 La Molina (UNALM), 26-29 November 2001, Lima, Peru. DM Jackson, attended the International Symposium, (abstract). “Sweetpotato, Food and Health for the Future,” Universidad Jackson, D. M. and J. R. Bohac. 2002. Resistance of Nacional Agraria La Molina, Lima, Peru, 26-29 Nov 2001. regional and standard sweetpotato entries to soil insects, Charleston, S.C., 2001. Pages 35-36 In W. D. McLaurin
(ed.), National Sweetpotato Collaborators Group Progress Jackson, D. M., J. R. Bohac, K. M. Dalip, J. Lawrence, D. Report, 2001. Clarke-Harris, L. McComie, J. Gore, D. McGlashan, P. Jackson, D. M., J. R. Bohac, and J. D. Mueller. 2002. Chung, S. Edwards, S. Tolin, and C. Edwards. 2001. Evaluation of advanced sweet potato entries for resistance to Integrated Pest Management of Sweetpotato in the soil insect pests, 1997. Arthropod Manage. Tests Volume Caribbean. Abstract BII-O-1 in Guide for Participants, 27, Report No. M-10. Online Journal at Sweetpotato: Food and Health for the Future, an http://www.entsoc.org/pubs/index.html. international symposium sponsored by the International Jackson, D. M., J. R. Bohac, and J. D. Mueller. 2002. Society for Horticultural Science (ISHA), the International Evaluation of advanced sweet potato entries for resistance to Potato Center (CIP), and the Universidad Nacional Agraria soil insect pests, 1998. Arthropod Manage. Tests Volume La Molina (UNALM), 26-29 November 2001, Lima, Peru. 27, Report No. M-11. Online Journal at (abstract). http://www.entsoc.org/pubs/index.html. Jackson, D. M., J. R. Bohac, K. M. Dalip, L. McComie, P. Jackson, D. M., J. R. Bohac, and J. D. Mueller. 2002. Chung, D. Seal, J. Mueller, D. Clarke-Harris, and F. D. Evaluation of advanced sweet potato entries for resistance to McDonald. 2002. Integrated pest management of major soil insect pests, 1999. Arthropod Manage. Tests Volume pests affecting sweetpotato, Ipomoea batatas, in the 27, Report No. M-12. Online Journal at Caribbean. Pages 127-147 In IPM CRSP, Integrated Pest http://www.entsoc.org/pubs/index.html. Management Collaborative Research Support Program, Jackson, D. M., J. R. Bohac, and J. D. Mueller. 2002. Eighth Annual Report, 2000-2001 (Management Entity, Evaluation of advanced sweet potato entries for resistance to Ed.). Virginia Polytechnic Institute and State University, soil insect pests, 2000. Arthropod Manage. Tests Volume Blacksburg, VA., 472 pages. 27, Report No. M-13. Online Journal at http://www.entsoc.org/pubs/index.html. Presentations Jackson, D. M., J. R. Bohac, and J. D. Mueller. 2002. Bohac, J. R., J. K. Peterson, D. M. Jackson, H. F. Harrison, Evaluation of advanced sweet potato entries for resistance to and M. E. Snook. 2001. Approach to selection of pest soil insect pests, 2001. Arthropod Manage. Tests Volume resistant sweetpotato breeding lines through identification 27, Report No. M-14. Online Journal at and quantitation of biochemical resistance compounds. http://www.entsoc.org/pubs/index.html. Internat. Symp., Sweetpotato, Food and Health for the Jackson, D. M., J. R. Bohac, and J. D. Mueller. 2002. Future, Universidad Nacional Agraria La Molina, Lima, Evaluation of regional sweet potato entries for resistance to Peru, 26-29 November 2001 (Presented by D. M. Jackson). soil insect pests, 1996. Arthropod Manage. Tests Volume Bohac, J. R., D. M. Jackson, J. K. Peterson, and H. F. 27, Report No. M-15. Online Journal at Harrison. 2002. Development of new sweetpotato breeding http://www.entsoc.org/pubs/index.html. lines with resistance to insects and other pests from the Jackson, D. M., J. R. Bohac, and J. D. Mueller. 2002. USDA program. Paper presented at National Sweetpotato Evaluation of regional sweet potato entries for resistance to Collaborators Meeting, 2 – 3 February, 2002, Kissimmee, soil insect pests, 1997. Arthropod Manage. Tests Volume Florida. (Presented by D. M. Jackson). 27, Report No. M-16. Online Journal at Jackson, D. M., J. R. Bohac, K. M. Dalip, J. Lawrence, D. http://www.entsoc.org/pubs/index.html. Clarke-Harris, L. McComie, J. Gore, D. McGlashan, P. Jackson, D. M., J. R. Bohac, and J. D. Mueller. 2002. Chung, S. Edwards, S. Tolin, and C. Edwards. 2001. Evaluation of regional sweet potato entries for resistance to Internat. Symp., Sweetpotato, Food and Health for the soil insect pests, 1998. Arthropod Manage. Tests Volume Future, Universidad Nacional Agraria La Molina, Lima, 27, Report No. M-17. Online Journal at Peru, 26-29 Nov 2001 (Presented by D. M. Jackson). http://www.entsoc.org/pubs/index.html. Jackson, D.M., J. R. Bohac, K. M. Dalip, J. Lawrence, D. Jackson, D. M., J. R. Bohac, and J. D. Mueller. 2002. Clarke-Harris, F. MacDonald, L. McComie, J. Gore, D. Evaluation of regional sweet potato entries for resistance to McGlashan, P. Chung, S. Edwards, S. Tolin, and C. soil insect pests, 1999. Arthropod Manage. Tests Volume Edwards. 2001. Sweetpotato IPM in the Caribbean. 39th 27, Report No. M-18. Online Journal at Annu. Sweetpotato Convention, Jan. 28-0, 2001, Orange http://www.entsoc.org/pubs/index.html. Beach, AL. (Poster presentation). Jackson, D. M., J. R. Bohac, and J. D. Mueller. 2002. Jackson, D. M. 2002. Sweetpotato IPM in the Caribbean. Evaluation of regional sweet potato entries for resistance to Poster presented at National Sweetpotato Collaborators soil insect pests, 2000. Arthropod Manage. Tests Volume Meeting, Feb. 2-3, 2002, Kissimmee, Florida. 27, Report No. M-19. Online Journal at Jackson, D. M., K. A. Sorensen, C. E. Sorenson, and R. http://www.entsoc.org/pubs/index.html. Story. 2002. Monitoring Diabrotica beetles in sweetpotato Jackson, D. M., J. R. Bohac, and J. D. Mueller. 2002. with floral lures. Paper presented at National Sweetpotato Evaluation of regional sweet potato entries for resistance to Collaborators Meeting, Feb. 2-3, 2002, Kissimmee, Florida. soil insect pests, 2001. Arthropod Manage. Tests Volume Jackson, D. M. 2002. Sweetpotato IPM in the Caribbean. 27, Report No. M-20. Online Journal at Poster presented at IPM CRSP Symposium 2002, Technical http://www.entsoc.org/pubs/index.html. Committee Meeting/ Year 10 Planning Workshop, 15-18 May 2002, Virginia Tech University, Blacksburg, VA.
Project Highlights An adult bioassay developed for evaluating sweetpotato germplasm for resistance to cucumber beetles indicated that In the United States, 63 sweetpotato entries were evaluated adults feeding on several insect-resistant sweetpotato for resistance to soil insect pests. The most promising of genotypes had significantly shorter lifespans than those that these entries were sent to St. Kitts and Jamaica for fed on the susceptible controls. evaluation under their cultural conditions. Improved sweetpotato germplasm was sent to Florida, St. Kitts, and Among 10 types of pheromone traps evaluated for Jamaica for evaluation under tropical conditions. Promising monitoring sweetpotato weevils (Cylas formicarius new insect trapping techniques were developed. elegantulus [Summers]), a modification of Talekar’s trap was most effective. Traps constructed from five-gallon pails At Bodles, Jamaica, 16 sweetpotato entries were evaluated or milk jugs also captured significant numbers of weevils. and most (including local entries) were found to be more tolerant to damage by sweetpotato weevils than the In February 2002, Extension Officers from the Ministry of susceptible checks ‘Beauregard’ and SC 1149-19. The Agriculture from the parish of St Elizabeth participated in a highest mean mass of tubers was obtained from TIS 30-30, one-day workshop and field day in the identification of the PI 531116 (from the breeding programme of the major pests of sweetpotato in Jamaica and their damage to International Institute for Tropical Agriculture in Nigeria) sweetpotato. Strategies used in an IPM programme were and Picadito, while 96-86 and 94-127 produced a also outlined. The participants also took part in an exercise significantly higher mean numbers of roots. to make pheromone traps and to place them in a farmer’s sweetpotato field. Several sweetpotato entries, such as 94-127, PI 531116, White Regal, Sidges, Tinian and TIS 30-30, showed The Department of Agriculture (DOA), St. Kitts held its resistance to sweetpotato leaf beetle larvae in Jamaica. open day in April 2002, while the DOA, Nevis staged theirs in May 2002. On both occasions, CARDI’s presentation PI531116, Picadito, Sidges and Fire-on-Land were among was “Sweetpotato Production, from field to factory”. It those entries with the greatest insect pest resistance. Tinian involved displays of some sweetpotato varieties, information (a new entry), though not a prolific producer, also showed on IPM and displays of processed sweetpotato products such high resistance to the insect pests and should be included in as chips, fries, etc., which were sampled by the public further trials. The regionalisation component of the sweetpotato IPM Promising new insect trapping techniques were developed under the project was continued with on-farm transfer of for spotted and banded cucumber beetles (Diabrotica spp.) IPM technology for the management of the sweetpotato and were found to be very efficient for monitoring the weevil. former.