Population Dynamics and Management of Brinjal Shoot and Fruit Borer, Leucinodes Orbonalis Guenee

Abstract

An investigation was carried out to study the "Population dynamics and management of brinjal shoot and fruit borer, Leucinodes orbonalis Guenee" during kharif, 2008 at Crop Research Centre, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut. The experiment comprised of eight treatments and laid out in randomized block design with three replications. During the crop season, eight insect pest species were found attacking the crop at different growth stages. Among them, brinjal shoot and fruit borer, L. orbonalis Guenee (August end to first week of January) was recorded as major pest. Leaf hopper, Amrasca biguttula biguttula Ishida (July end to last week of December), Cotton aphid, Aphis gossypii G. (fourth week of August to first week of January) and white fly, Bemisia tabaci Gennadius (last week of July to first week of December) were found moderately damaging the crop. The leaf roller, Eublemma olivacae W. (second week of September to second week of November), epilachna beetle, Epi/achna vigintioctopunctata Fab. (last week of July to third week of December), leaf webber, Psara bipunctalis F. (fifth week of August to fourth week of October) and grass hopper, Chrotogonus spp.(last week of July to third week of December) recorded on the crop were of less importance. The population of L. orbonalis recorded first on first week of September and continued till last week of December. Highest population of the pest (5.40 larvae/ plant) recorded during last week of October. When average temperature and relative humidity were 22.46°C and 70.07 per cent, respectively. Efficacy of different insecticides revealed that all the treatments proved better than control at all time intervals after each sprays. Cypermethrin 25 EC @ 0.007 per cent was found most effective in reducing the infestation of L. orbonalis which was closely followed by dimethoate 30 EC @ 0.05 per cent and endosulfan 35 EC @ 0.05 per cent. Neem oil @ 0.2 per cent was recorded less effective. The highest yield (250.1 0 q/ha) and higher cost benefit ratio (1 :20.02) were also obtained from cypermethrin 25 ~C @ 0.007 per cent.