Bioefficacy of new insecticide molecules against cotton jassid, Amrasca biguttula biguttula and whitefly, Bemisia tabaci

摘要

An experiment was conducted to evaluate the efficacy of few new groups of insecticides against two important sucking pests of cotton viz., cotton jassid ("Amrasca biguttula biguttula) and whitefly ('Bemisia tabacij during the pre-Kharif season of 2011and2012. The insecticides viz., imidacloprid 17.8% SL @ 18, 27 & 36g~(-ha), spiromesifen 24 % SC @ 100, 150 & 200 g~(-ha) and buprofezin 25% SC @ 150, 200 & 300 g~(-ha)were applied two times at 15 days interval. Among the treatments, the most effectiveinsecticide in controlling the jassid population was buprofezin @ 300 g~(-ha) followed by imidacloprid @ 36 g~(-ha) and least effective was spiromesifen @ 100 g~(-ha). The order of bioefficacy on the basis of per cent reduction of cotton jassid over control plot was: buprofezin > imidacloprid > spiromesifen. But in case of whitefly, the most effective insecticide was spiromesifen @ 150 g followed by buprofezin @ 300 g~(-ha) and least effective was buprofezin @ 150 g. The order of bioefficacy on the basis of per cent reduction of cotton whitefly over control was, spiromesifen > buprofezin > imidacloprid.