Biological characteristics and parasitization potential of Encarsia formosa Gahan (Hymenoptera: Aphelinidae) on the whitefly, Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae), a pest of greenhouse crops in north-western Indian Himalayas

Abstract Background The greenhouse whitefly, Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae) constitutes key pests of greenhouses and field crops, which have developed pesticide resistance over the years. It has emerged as a difficult pest to manage owing its indiscriminate exposure higher dosages insecticides. use natural enemies is environmentally safe alternative management tactic. Efficacy Encarsia formosa Gahan (Hymenoptera: Aphelinidae) was determined by studying biological characteristics on T. . Results Parasitization E. fourth-instar nymphs whitefly (GHWF) (37.2%), at par with that third instar (36.4%), both differing significantly parasitization observed in second (19.6%). Total developmental duration parasitoid longer (33.2 days) than fourth (29.9 days). Adult longevity found for adults from GHWF, absence host. size different instars GHWF varied non-significantly. reared brinjal, cucumber, French bean, lettuce, tobacco, tomato plants mass production Among them, bean tobacco were be best host based (37.2%). period 26.4 27.3 days plants, variations being non-significant. maximum adult cucumber (8.0 host, ratio 5:1, 10:1, 20:1, 40:1 80:1 revealed rate 61.2 95.0% recorded host–parasitoid proportion 20:1 minimum 80:1. total non-significantly among all proportions (15.1–15.4 (6.5 days), 5:1 (6.2 10:1 (6.1 respectively. Conclusion This study suggests augmentative control under polyhouse conditions appears an effective strategy this economic pest.