MANAGEMENT OF HADDA BEETLE, EPILACHNA VIGINTIOCTOPUNCTATA (FABR.) ON BRINJAL AND BITTER GOURD

Management of Hadda beetle, Epilachna vigintioctopunctata (Fabr.) on brinjal and bitter gourd Vishav Vir Singh Jamwal, J-06-D-51-A Entomology Dr. Hafeez Ahmad Associate Professor Ph.D. Entomology 2011 Sher-e-Kashmir University of Agricultural Sciences & Technology Jammu (J&K) Title of the Thesis Name of the Student and Admission No. Major Subject Name and Designation of Major Advisor Degree to be awarded Year of award jf Degree Name of the University ABSTRACT Studies on the management of hadda beetle, Epilachna vigintioctopunctata fTabr. ) on brinjal and bitter gourd were conducted at the University Research Farm, Division of Entomology, SKU.AST-J, Main Campus, Chatha, Jammu during 2008 and 2009. The studies on host range revealed that the 16 cultivated and 3 wild plants growing in the vicinity of the brinjal and bitter gourd offer shelter to the pest and maintain its population throughout the year. On the basis of growth index, Physalis minima was found to be the most suitable host plant followed by Solanum nigrum, S. melongena, 5. tuberosum, Lycopersicon esculentum, Momordica charantia. Datura stramonium. Luffa cylindrica was the least preferred host plant. Seasonal abundance evidenced that the pest remained active from April to October during 2008 and 2009 and the highest number of grubs (3.78 grubs/ plant) and adult beetle population (5.48 adults/ plant) was recorded in the 35"' and 36"" standard week, respectively. Regression studies showed that overall influence of all the major weather parameters was 35.9 per cent on egg clusters but the effect of abiotic factors on the build up of grub population was 87.3 per cent. The grub population was significant and positively correlated with average minimum temperature (r = 0.617), morning relative humidity (r = 0.667) and evening relative humidity (r = 0.840). The pupal population was significantly correlated with average minimum temperature (r = 0.752) and evening relative humidity (r = 0.586) having 66.8 per cent influence on population. Adult population showed significant correlation with average minimum temperature (r = 0.515), morning relative humidity (r = 0.669) and evening relative humi.lity (r = 0.796) with 81.9 per cent influence. Bionomics of the pest on brinjal and bitter gourd crops revealed that after the mating period of 61.35±19.44 and 64.50±18.02 minutes; 55.35±19.65 and 60.75±24.25 minutes for two subsequent generations, the female started laying eggs during first and second generations on both the crops, respectively. Eggs were laid in clusters mostly on the under side of the leaves and a single female laid on an average of 223.60±39.33 in 1*' and 241.80±24.50 in 2'""generation; 203.20±32.99 in l" and 213.10±31.63 in 2"'' generation, during oviposition period of I3.20±1.03 in 1'' and I3.60±1.26 in 2"'' generation; 11.30±0.67 in l" and 11.80±0.92 days in 2"'' generation on brinjal and bitter gourd, respectively. The grubs passed through four instars and the total duration lasted for 13.70±1.89 in l"and 14.30±1.70 in 2"'' generation, 15.90±1.29 in l" and 16.80±1.81 days in 2'"' generation on brinjal and bitter gourd. The total developmental period from egg to adult emergence varied from 22.80±3.05 in 1" and 23.90±2.42 in 2"" generation; 26.30±1.89 in l" and 27.80±2.65 days in 2"'' generation on both the crops, respectively. Longevity of adult male was 12.60±2.22 in l" and I3.60±1.57 in 2"''generation; 9.20±0.79 in T' and 9.60±0.97 days in 2"'' generation, while for female it was 30.90±3.86 in T' and 32.10±1.66 in 2"'' generation; 26.20±1.62 in T' and 28.10±1.48 days in 2"'' generation on brinjal and bitter gourd, respectively. Studies conducted for management of hadda beetle revealed that carbaryl 50WP (0.10%) proved to be the most effective treatment for two consecutive years on brinjal and bitter gourd in terms of highest cost benefit ratio (1:34.00 and i:29.00) and yield (345 and 110 q/ ha) However, fipronil 5SC (1:26.00 and 1:22.27) and lamda cyhalothrin 5SC (•.:24.24 and 1:19.39) were equally effective. Beauveria bassiana 1.25WP. Steinernema carpocapsae @ 2 billion Us/ ha and NSKE 5% also significantly suppressed the pest population but had low cost benefit ratio of (1:20.82 and 1:23.00), (1:9.80 and 1:9.20) and (1:11.31 and 1:10.08), respectively. Wood ash can be a good alternative for resource poor farmer or organic growers as the same could protect the crop with cost benefit ratio of (1:7.0 and 1:9.2). However, all the treatments were effective in reducing the pest population and increase in the marketable yield of the crops.