Evaluation of insecticides against whitefly on tomato and their effect on natural enemies

The study was conducted during tomato growing season of 2011 and 2012 in Jama block of Dumka district of Jharkhand to evaluate the effectiveness of imidacloprid as seed/root treatment and spraying of same insecticide or followed by Dimethoate as foliar application against the whitefly (Bemisia tabaci) after analysis of technological gap of package of practice of tomato cultivation. The experimental result revealed that the root treatment done with Imidaclorprid70 WS solution @ 3 g/L of water for 30 minutes followed by one spray with Imidaclorprid 17.8 SL@ 0.3 ml/L and second spray with Dimethoate 30 EC @1.5ml/L water was more effective in reduction of whitefly population to obtain higher fruit yield of tomato than by seed treatment done with Imidaclorprid 70 WS @ 3g/kg of seed and 2 sprays done with Dimethoate 30 EC @1.5ml/L water. Both the insecticides showed no or minimum suppression of coccinellid & spider population. Hence, neonicotinoids can suitably be included in Integrated Pest Management of sucking insect pests like whitefly in tomato because of their less toxicity to predators