A combination of predator and selective pesticide improves control of resistant Aphis gossypii (Hemiptera: Aphididae).

Abstract

The cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is a major pest in cotton production, notorious for its rapid development of resistance to pesticides, which complicates control efforts. A sustainable solution involves combining selective insecticides with biocontrol agents to reduce pest populations while preserving natural enemies. Afidopyropen, a novel transient receptor potential vanilloid-targeted insecticide, was extremely safe for the minute pirate bug Orius sauteri Poppius (Hemiptera: Anthocoridae), a common predator of small pests. The LC50 values for direct exposure were 592.38, 497.02, and 382.71 mg/L for the fifth instars and female and male adults, respectively. Even at the maximum recommended field rate, afidopyropen had minimal impact on the survival, predation efficiency, and reproduction of pesticide-treated O. sauteri and their offspring. Despite the resistance observed in field-collected A. gossypii, combining a low concentration of afidopyropen with O. sauteri significantly reduced aphid populations. By day 7 post-treatment, aphid density was decreased by over 94.29%. While a higher concentration of afidopyropen initially achieved 98.19% control, aphid populations rebounded over time. This study demonstrated that afidopyropen was extremely safe for O. sauteri as indicated by the higher LC50 values. The combination of a low concentration of afidopyropen with O. sauteri offers an effective control approach for resistant A. gossypii, presenting a novel integrated pest management strategy.