Role of multiple detoxification enzyme genes in Nitenpyram resistance of Nilaparvata lugens

The brown planthopper (BPH), Nilaparvata lugens , is a major insect pest of rice. Nitenpyram, a neonicotinoid insecticide, is a key compound for its control. Understanding the underlying resistance mechanisms is critical for developing effective management strategies. In this study, a nitenpyram-resistant (NR) N. lugens strain was established and characterized. Synergism tests and detoxification enzyme assays collectively demonstrate that enhanced metabolic detoxification plays a pivotal role in nitenpyram resistance in N. lugens . Quantitative RT-PCR (qRT-PCR) analysis revealed the significant overexpression of multiple candidate genes in the NR strain, including an ABC transporter gene ( ABCG1 ), four P450 genes ( CYP6ER1 , CYP3115A1 , CYP417A2 , and CYP418A1 ), four CarE genes ( CarE2 , CarE7 , CarE15 , and CarE26 ), and a UGT gene ( UGT 2B9 ). Additionally, molecular docking and molecular dynamics simulations further corroborated the high binding affinity and structural stability of these enzymes (ABCG1, CarE7, CarE15, CYP6ER1, CYP3115A1, CYP417A2, CYP418A1) and nitenpyram. Functional validation via RNA interference (RNAi) showed that silencing of ABCG1 , CarE15 , CYP3115A1 , CYP418A1 , and CYP6ER1 significantly increased nitenpyram susceptibility, confirming their functional role in resistance. Collectively, these findings elucidate a metabolic resistance mechanism mediated by multiple detoxification enzyme genes upregulation and provide a scientific basis for optimizing resistance management strategies to prolong the efficacy of nitenpyram in rice ecosystems.