Comparative Efficacy of Biopesticides and Chemical Insecticides against Myzus persicae (Sulzer) and Bemisia tabaci (Gennadius) in Potato Crop under Western Uttar Pradesh Conditions

Abstract

A field experiment was conducted during the Rabi season of 2021–22 at the Crop Research Centre, Chirori, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut, Uttar Pradesh, to compare the efficacy of selected biopesticides and chemical insecticides against Myzus persicae and Bemisia tabaci in potato. Seven treatments, namely neem oil, Beauveria bassiana, Difenthiuron 50 WP, Thiamethoxam 25 WG, Pymetrozine 50 WG, Imidacloprid 17.8 SL, and an untreated control, were evaluated in a randomised block design with three replications. Two foliar applications were made at 30 and 45 days after planting, and pest populations were recorded before spraying and at 5 and 10 days after each application. Based on the overall mean across both sprays, Pymetrozine 50 WG at 300 g/ha recorded the lowest aphid population, with 1.35 aphids per three leaves per plant. Difenthiuron 50 WP at 500 g/ha recorded the lowest whitefly population, with 0.99 whiteflies per three leaves per plant. Thiamethoxam 25 WG and Imidacloprid 17.8 SL were the next most effective treatments against both pests, whereas Beauveria bassiana and neem oil provided moderate suppression. All evaluated treatments significantly reduced pest populations compared with the untreated control. The findings indicate that Pymetrozine and Difenthiuron may be considered effective components of integrated management programmes for aphids and whiteflies, respectively, in potato under Western Uttar Pradesh conditions.