EFFECT OF INDISCRIMINATE USE OF INSECTICIDES ON INSECT FAUNA ON COTTON

Flonicamid 50 % WG and buprofezin 25 % SC was showing effective reduction of pest population among all the treatments and found very effective treatments for pests like jassid, thrips, whitefly, aphid on Bt cotton. The rate of reduction of jassid population in imidacloprid 17.8 % SL and Lamda-cyhalothrin 5 % EC was lower than other treatments. Lamda-cyhalothrin 5 % EC and fipronil 5 % SC gave control of whiteflies after each spraying for 3-7 days, but later on the population increased rapidly as compared to other insecticides. Natural enemies observed predominantly on Bt cotton during Kharif 2017-18 were ladybird beetle and chrysopa. Flonicamid 50 % WG, buprofezin 25 % SC, spinosad 45 % SC and spinoterum 11.7 % SC were more safe for ladybird beetle and chrysopa than other insecticides. Pink bollworm damage was more during this Kharif season. Lamda-cyhalothrin 5 % EC found very effective in reducing population of these bollworms, also spinotrum 11.7 % SC, spinosad 45 % SC found and acephate 75 % SC effective against pink bollworm.