Uridine Diphosphate-Glycosyltransferase RpUGT344D38 Contributes to λ-Cyhalothrin Resistance in .

Uridine diphosphate-glycosyltransferase (UGT) is a key phase II enzyme in the insect detoxification system. Pyrethroids are commonly used to control the destructive wheat aphid . In this study, we found a highly expressed UGT gene, 34438, in both λ-cyhalothrin (LCR)- and bifenthrin (BTR)-resistant strains of . After exposure to λ-cyhalothrin and bifenthrin, the expression levels of 34438 were significantly increased in the resistant strains. Knockdown of 34438 did not affect the resistance of BTR, but it did significantly increase the susceptibility of LCR aphids to λ-cyhalothrin. Molecular docking analysis demonstrated that RpUGT344D38 had a stable binding interaction with both bifenthrin and λ-cyhalothrin. The recombinant RpUGT344D38 was able to metabolize 50% of λ-cyhalothrin. This study provides a comprehensive analysis of the role of 34438 in the resistance of to bifenthrin and λ-cyhalothrin, contributing to a better understanding of aphid resistance to pyrethroids.