Bio-efficacy of insecticides and bio pesticides against major sucking pests of Bt- cotton

Abstract

The present experiment was carried out in insectary farm, Section of Entomology, College of Agriculture, Nagpur during 2016-2017 to evaluate the efficacy of different treatments (chemicals, botanicals and microbials viz. Imidacloprid 17.8 SL, Spiromesifen 22.9 SC, Neem oil 2%, Neem seed extract 5%, Tobacco leaf extract 10%, Metarhizium anisoplie 1x108 CFU/ml, Verticillium lecanii 1x108 CFU/ml and Beauveria bassiana 1x108 CFU/ml) against sucking pest complex of cotton. Highest reduction in mean nymph population of sucking pests (except whitefly) was recorded with Imidacloprid 17.8 SL (aphids-79.55%, 78.28%; jassids- 77.32%, 75.50%; thrips- 78.94%, 77.88%) followed by Spiromesifen 22.9 SC (aphids- 73.18,70.90; jassids-73.05, 71.82; thrips- 76.30,74.20) after 5 and 10 days of all three sprayings respectively. Whereas, highest reduction in the population of whitefly was observed in Spiromesifen 22.9 SC (82.27%, 80.57%) followed by Imidacloprid 17.8 SL (78.32%, 77.90%). Among botanicals, Neem oil 2 per cent, Neem seed extract 5 per cent and Tobacco leaf extract 10 per cent were found effective towards reduction of sucking pests. Whereas, amongst the microbials Metarhizium anisoplie 1x108 CFU/ml was found promising for controlling jassids and Verticillium lecanii 1x108 CFU/ml against aphids, whitefly and thrips.