Plant Sciences
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PLANT SCIENCES Plant and Environment Protection Identification of Resistance Sources in Wheat National Wheat Disease Screening Nursery Four hundred and fourteen wheat lines including 99 commercial wheat varieties were planted at 10 key locations in the country. Eighteen commercial wheat varieties and 108 advance lines were found resistant to both leaf and yellow rusts while 58 commercial wheat varieties and 139 advance lines were found effective against prevailing races of leaf rust. National Uniform Wheat Yield Trial Total thirty candidate lines received from the National Coordinated Wheat Programme were planted at 13 key locations in the country to evaluate against rusts of wheat. Out of 30 candidate lines, 4 lines were found susceptible, 12 lines resistant to moderately resistant, 6 lines moderately susceptible and 8 were found immune. Screening of Wheat Cultivars Against Karnal Bunt (KB) National Wheat Disease Screening Nursery (NWDSN) was comprised of 414 wheat lines including 99 commercial varieties and 292 breeders advance lines. Eighty three lines were found free of KB including 10 commercial wheat varieties and 73 advanced lines of breeders. Ten lines from CIMMYT which were found free of KB last year were tested again in field, only three lines were found free of KB. Thirty candidate lines of NUWYT 2010-11 nurseries were evaluated under field conditions and four lines were found free of KB. Study of Current Status of KB in Punjab and KPK Two hundred and twenty samples from Punjab and 40 samples from KPK were collected for determination of prevalence and incidence of the disease. In Punjab, the prevalence of KB was 15 % and incidence ranged from 0-1%. Whereas in KPK the disease prevalence was 12.5 % and incidence ranged from 0-0.9%. The KB infected seeds from these samples were used to isolate the fungus Tillitia indica for morphological studies, pathogenic variability and identification of source of resistance. So far 5 isolates have been isolated, identified and purified. Epidemiology of Wheat Rust Virulence Studies Isogenic leaf and yellow rust wheat lines were planted at 13 locations in Pakistan for virulence studies. Virulence for yellow rust resistant genes Yr1, Yr2, Yr6, Yr7, Yr9, Yr17, YrA and Yr27 were present at all locations. For genes (Yr3), Yr5, Yr10, Yr15, Yr26, YrSP (Spaliding Prolific) and YrCv (Castrens V) virulence factors were not observed in field during this year, these genes are effective genes and recommended as resistance source for ANNUAL REPORT 2011-12 03 Plant and Environment Protection introgression. Virulence for leaf rust resistant genes Lr22B, Lr1, Lr2a, Lr2b, Lr2c, Lr3, Lr3ka, Lr3bg, Lr9, Lr10, Lr11, Lr12, Lr13, Lr14a, Lr14b, Lr15, Lr16, Lr17, Lr18, Lr19, Lr20, Lr23, Lr24, Lr25, Lr26, Lr27+31(Gatcher)Lr29, Lr30, Lr32, Lr33, Lr34, Lr35and Lr13+ were in all locations in Sindh, Punjab and Khyber Pakhtunkhwa. Leaf rust resistance genes Lr28, Lr36 and Lr37 showed avirulence at all locations. Total 20 Leaf rust samples were collected from trap nurseries and farmers fields and all samples were revived. Thirty single pustules were made and each pustule was multiplied. Two different races TKT/RP and TKT/RN were identified. 15 Yellow rust samples were collected and multiplied for virulence analysis. Two different races 80E85 and 70E0 were identified. 30 stem rust samples were evaluated and race RRTTF was identified and confirmed the absence of UG-99 in Pakistan. Bacterial Blight of Rice A survey of selected districts of Punjab was conducted to determine the current status of bacterial blight. The incidence percentage ranged from 0-90, 0-100, 0-75, 0-70, 0-25 and 0- 100 in Sialkot, Narowal, Sheikhupura, Gujranwala, Hafizabad, and Zafarwal, respectively. Mycotoxin in Groundnut A survey for the incidence of mycotoxin producing fungi in groundnut under storage conditions at different locations (Punjab: District Rawalpindi, Attock, Chakwal, Jehlum), & Khyber Pukhtunkhwa (Kohat) of Pakistan showed the presence of 7 fungi viz., Alternaria, Aspergillus flavus, Aspergillus niger, Penicillium, Trichoderma, Fusarium graminearum, Fusarium oxysporum in groundnut farmer's fields and storage centres. Mapping was done for the incidence of aflatoxins producing fungi in groundnut at market and consumer level in Pothwar areas. Viral Studies Screening of Tomato Germplams Against Viral Diseases In a replicated experiment of five tomato hybrid/lines grown under plastic tunnel at NARC, cultivar Sahil was found free from virus like symptoms and was without insect infestation. Screening of Potato Germplasm Against Six Viruses under Field Conditions In a replicated trial of twenty potato varieties, only one variety, Sarpo-Mira was found free from virus infection followed by NARC 17-19 with an infection rate of 10% with PVY. PLRV was not detected in the germplasm. Screening of Garlic Germplasm Against Viruses Data were recorded on garlic germplasm sown in NARC field for rust and smut appearance. Iranian, Italian and MJ-84 showed 50 % of rust and 100% of smut infection. Chinese variety 04 ANNUAL REPORT 2011-12 Plant and Environment Protection showed 100 % rust and smut infection. Only NARC-09 was apparently free from rust and smut infection. Maximum size of the bulb of Chinese, Italian, Iranion, JS-1 and NARC-09 were 8,2, 9.2 8.4, 6.2, 8.5 cm respectively with an average number of 12 cloves each. Six exotic/local garlic germplasm (Chinese, Iranion, Italian, JS-1, NARC-09 and Local ) were screened under natural conditions. It was observed that cultivar elephant garlic (NARC 09) was highly resistant to OYDV. In addition, five plants of Italian and four of Iranian origin were found clean from viral infection. Insect Pest Management · Seedling Bulk Test of NUWYT-N 2011-12 was conducted to find out for resistance against Corn Leaf aphid; wheat line PR-102, V-05BT006 and BGWS-4 was found to be resistant. Antixenosis test of same lines showed that least preferred entries were V- 08173, V-07076, V-76309 and V-05BT006. In Antibiosis test: Entries V-07096, V- 07076, V-08171, V-0587014, SD-076309, 076377, CT-04192, TW-96007, HB-10, HB-11, PR-102, QS-111, NR-378, and NARC L. Check were least fecund. Bird cherry oat aphid Mass rearing Seedling Bulk test Antixenosis Test Antibiosis Test Tolerance Test · Screening of NUWYT-RF 2011-12: Resistant entries were NRL-0517, DN-73 and NR-397. In Antixenosis test moderately preferred entries were NRL-0517, AZRC- 2008-1, NR-381, NR-390 and NR-391. In Antibiosis test least fecund entries were NR- 397, AZRC-2008-1, 6-C016, NR-397, NR-392 and L. check. In Tolerance test comparatively tolerant entries were KT-50 and NR-397. · Evaluation of Maize Varieties: Varieties AGT-2002, EV 1098, EV 6098, Sadaf and Raka Poshi were resistant. In Antixenosis test best variety was Sahiwal-2002 followed by EV 1097, AGT-2002, BS-2, EV 6098 and Islamabad Gold. · Seedling Bulk Test of Maize Hybrids: P-1543, NARC-2704 and JKMH-444 were found to be resistant. In Antixenosis results, NARC-2704, KERMESS (KWS), MT-1, ANTISS and AF-GOI were least preferred (LP). · Screening of Oats Varieties: Avon, V- 97009, V-663, V-2088 and Stamped were resistant. In Antixenosis results Dumont, Grizzly, 663, 85-125, 75526, Mar.100, Canadian, Grizzly, 11xs-81, 2088 and Nora were found to be least preferred against corn leaf aphid. In Antibiosis test: PD2-LV65, Avon, Canadian, 85-125, 663,Grizzly and S-141 were least fecund. · Control of Red Pumpkin Beetle with Neem Water Extract Compared with Surf Emulsion and Deltamethrin: After chemical spray best results for beetle control were observed with application of 2% spray of neem as compared to 0.5% of neem extract, control and surf emulsion. · Laboratory Studies for Repellency Against Cotton Mealy Bug: Mentha piperata, Citrullus colocynth, Ricinus communis, Sonchus oleraceous, Silybum marianum, Acacia Senegal, Trachyspermum ammi, Xanthium strumarium, Cnicus benedictus, ANNUAL REPORT 2011-12 05 Plant and Environment Protection Cassia fistula, Carica papaya were tested on 1st and 2 nd instars Cotton mealy bug after first, second, fourth and eighth week of extract application. Cottn mealy bug repellency studies · Biological Observations and Predatory Potential of Coccinellid Beetles Harmonia Dimidiata, Menochilus Sexmaculatus and Coccinella Septempunctata Feeding on Different Aphid Species: Harmonia dimidiate: The larval/grubs developmental duration and survival rate at four different temperature were 21.3,17.7,14.7 and 12.3 days at 20 ±1 °C, 24 ±1 °C, 28±1 °C and 32±1 °C. The survival rates were 92, 90, 78 and 62% and the predatory potential were 934, 856, 644 and 573 aphids/grubs. Adult longevity were 120, 95, 72 and 24 days with total fecundity of 956, 1234, 678 and 0 eggs at four temperature levels. Adult predatory potential were 9634, 10076, 7543 and 944 aphids/adult. Grubs of Harmonia dimidiate, Manochilus sexmaculatus and Coccinella septempunctata. Menochilus Sexmaculatus: Development duration of M. sexmaculatus, feeding R. padi under laboratory condition indicates eggs duration was 3.4 days, while 1st , 2 nd , 3 rd and 4th instars were 2.3, 2.5, 3.4 and 4.1 days respectively and pupal duration was 6.7 days and predation capacity of 1st , 2 nd , 3 rd , and 4 th instars were 11.5 aphids, 19.4, 47.4 and 71.2 aphids per larvae respectively under laboratory condition. The adult female life stages indicate that pre-oviposition period was 5.2 hours, copulation period was 51.4 minutes and post-copulation period was 3.1 hours. Pre-ovipositon period was 5.3 days, oviposition period was 35.4 days and post-oviposition period was 5.4 days respectively. Fecundity, incubation and eggs hatching percentage of M. sexmaculatus indicates that fecundity was 376 eggs per female with incubation period of 3.8 days and hatching percentage of eggs was 67.8.