Bioefficacy of different insecticides against pests and harvest time residues in Brinjal fruits

Abstract

An experiment was conducted to study the bioefficacy of six different insecticides (thiamethoxam 25 WG @ 0.01%, thiacloprid 21.7 SC @ 0.0032%, buprofezin 25EC @ 0.05%, spinosad 48 SC @ 0.017%, chlorantraniliprole 18.5 SC @ 0.007% and fenpropathrin 30 EC @ 0.01%) with a control (water spray) against sucking pests, viz., shoot and fruit borers, jassids, whiteflies and aphids, and harvest time residues in brinjal (Surti Ravaiya) at the College Farm, North Asian University, and Navsari during summer-2020. Among the different insecticides evaluated, chlorantraniliprole and spinosad were the most effective, fenpropathrin and buprofezin were the least effective insecticides against shoot and fruit borers, respectively. Thiamethoxam and thiacloprid were the most effective agents. Fenpropathrin and buprofezin were the least effective against whiteflies, jassids and aphids. After two hours of spray, the initial deposition order of the experimental insecticides was buprofezin (10.382 mg/kg) > fenpropathrin (5.602 mg/kg) > chlorantraniliprole (5.097 mg/kg) > thiamethoxam (4.886 mg/kg) > spinosad (3.984 mg/kg) > thiacloprid (3.332 mg/kg), while after 4 days of spray, the residue status of the brinjal fruit was in the order of fenpropathrin (0.539 mg/kg) > chlorantraniliprole (0.154 mg/kg) > thiacloprid (0.127 mg/kg) > thiamethoxam (0.099 mg/kg) > buprofezin (0.076 mg/kg) > spinosad (BDL). Overall, the highest percentage degradation of insecticide residues in brinjal fruits was registered with spinosad (100%), followed by buprofezin (99.26%), thiamethoxam (97.97%), chlorantraniliprole (96.97%), thiacloprid (96.18%) and fenpropathrin (90.37%) after 4 days of II spray.