Two detoxification enzyme genes, CYP6DA2 and CarFE4 , mediate the susceptibility to afidopyropen in Semiaphis heraclei

is an important economic pest affecting Caprifoliaceae and Apiaceae plants, and chemical control is still the main effective control method in the field. Afidopyropen is a new type of pyridine cyclopropyl insecticide, which can effectively control piercing-sucking mouthparts pests and is suitable for pest resistance management. However, the detoxification mechanism of . to afidopyropen is still poorly cleared. The insecticidal activity of afidopyropen against and the enzyme activity assay and synergism bioassay were evaluated. The detoxification enzyme genes were obtained by transcriptome and validated by quantitative real-time PCR (RT-qPCR). Furthermore, RNA interference was used to study the functions of detoxification enzyme genes. The activities of cytochrome P450 monooxygenases (P450s) and carboxylesterases (CarEs) were significantly increased under afidopyropen treatment. The toxicity of afidopyropen against was significantly increased after application the inhibitors of piperonyl butoxide and triphenyl phosphate. Sixteen P450 genes and three CarE genes were identified in the transcriptome of . The RT-qPCR results showed that eleven P450 genes and two CarE genes were significantly upregulated under afidopyropen treatment, and the expression of and was upregulated by more than 2.5 times. The expression pattern of and was further analyzed in different developmental stages of and knockdown of and significantly increased the susceptibility of to afidopyropen. The results of this study uncover the key functions of and in the detoxification mechanism of to afidopyropen, and provide a theoretical basis for the scientific use of afidopyropen in the field.