Abstract:

To promptly understand the development of resistance in whitefly, a major pest in tomato greenhouses in Lanxi City, to conventional pesticides, and to screen for highly effective, safe, and low-toxicity pesticides for controlling greenhouse whiteflies, laboratory toxicity bioassays and field trials were conducted to compare the toxicity and control efficacy of eight pesticides against adult whitefly. The results revealed significant differences in toxicity among the tested pesticides. Among them, 25% nitenpyram SP maintained relatively high toxicity against adult whiteflies, with an average LC₅₀ of 1.58 mg·L^-1. In contrast, adult whitefly exhibited low sensitivity to 22% thiacloprid WG and 1.3% matrine AS, particularly the latter, which had an average LC₅₀ of 75.92 mg·L^-1. Field trial results demonstrated that 25% Nitenpyram SP, 20% dinotefuran WP, 70% imidacloprid WG, and 10% flonicamid WG all showed superior control efficacy at 7 and 14 days after application. Given the significant variation in the susceptibility of greenhouse whitefly adults to different pesticides and combined with laboratory toxicity data, 25% nitenpyram SP, 20% dinotefuran WP, 70% imidacloprid WG, and 10% flonicamid WG are recommended as effective pesticides for controlling whitefly in greenhouses in Lanxi City.

Key words: pesticides, whitefly, toxicity, control efficacy