Field efficacy of various insecticides against major sucking pests of Bt cotton

Ten insecticides were evaluated against major sucking pests infesting the Bt cotton. Among them five were of bio-pesticides (Neem oil 1.0 %, NSKE (Neem seed kernel extract) 5.0 %, Azadirachtin 0.0009 %, Verticillium lecanii (Zimmermann) @ 2.5 kg/ha and Beauveria bassiana (Balsamo.) @ 2.5 kg/ha) and five were chemical pesticides (Acetamiprid 0.004 %, Thiamethoxam 0.01 %, Imidacloprid 0.0089 %, Dinotefuran 0.008 % and Flonicamid 0.02 %) at KVK farm, JAU, Targhadia (Rajkot) during Kharif, 2012-13. The result on the field efficacy of newer insecticides against major sucking pests of Bt cotton (G Cot Hy 6 BG II) showed that the chemical pesticides caused higher mortality, while bio-pesticides caused moderate to lower mortality of sucking pests. Among the insecticidal treatments, flonicamid 0.02 per cent was found more effective against all major sucking pests, acetamiprid 0.004 per cent against aphid and whitefly, dinotefuran 0.008 per cent and imidacloprid 0.0089 per cent against jassid and thiamethoxam 0.01 per cent were found effective against thrips on Bt cotton. Among the bio-pesticides, neem oil 1.0 per cent, V. lecanii @ 2.5 kg/ha and azadirachtin 0.0009 per cent were found moderate effective against major sucking pests of Bt cotton. In case of toxicity of insecticides on predators (Coccinellids and Chrysoperla) of sucking pests, all the bio-pesticides were found safer to predators, while chemical pesticides were found moderate to higher toxic to predators on Bt cotton.