Efficacy of Botanicals and Bio-Pesticides on Population Dynamics of Bollworm Complex and their Safety to the Predators in Non-bt Cotton

Abstract

A field investigation was carried out to assess the population fluctuation of bollworm complex and their natural enemies on non-Bt cotton. Twenty treatments including four botanicals were evaluated initially against sucking pests and continued further for check against bollworm complex with scheduling HaNPV, Bt and spinosad. The minimium egg and larval population of Helicoverpa armigera was reported in the application of NSE 5% and Azadirachtin 1500 ppm followed by spinosad 45 and HaNPV 250 LE/ha. However, the application of NSE 5% and Azadirachtin 1500 ppm followed by spinosad 45 SC was better in reducing larval population of Easias vitella. The treatment schedules comprising four botanicals followed by spinosad 45 SC as well as Bt 1000 g/ha have been found effective in reducing the larval population of pink bollworm in green bolls. The sole treatments of botanicals and the applications of botanicals followed by HaNPV 250 LE/ha have been observed to be safer to adults of coccinellids beetles, Chrysoperla zastrowi sillemi eggs and larvae as well as spiders.