Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China.
Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China.
Pestic Biochem Physiol. 2019 Jun;157:26-32. doi: 10.1016/j.pestbp.2019.03.001. Epub 2019 Mar 5.
Nitenpyram is very effective in controlling Nilaparvata lugens (brown planthopper, BPH), and its resistance has been reported in field populations; however, the resistance mechanism remains unclear. In the present study, cross-resistance and resistance mechanisms in nitenpyram-resistant BPH were investigated. A resistant strain (NR) with a high resistance level (164.18-fold) to nitenpyram was evolved through successive selection for 42 generations from a laboratory susceptible strain (NS). The bioassay results showed that the NR exhibited cross-resistance to imidacloprid (37.46-fold), thiamethoxam (71.66-fold), clothianidin (149.17-fold), dinotefuran (98.13-fold), sulfoxaflor (47.24-fold), cycloxaprid (9.33-fold), etofenprox (10.51-fold) and isoprocarb (9.97-fold) but not to triflumezopyrim, chlorpyrifos and buprofezin. The NR showed a 3.21-fold increase in cytochrome P450 monooxygenase (P450) activity compared to that in the NS, while resistance was also synergized (4.03-fold) with the inhibitor piperonyl butoxide (PBO), suggesting a role of P450. Furthermore, the mRNA expression levels of cytochrome P450 (CYP) genes by quantitative real-time PCR results indicated that twelve P450 genes were significantly overexpressed in the NR strain, especially CYP6ER1 (203.22-fold). RNA interference (RNAi) suppression of CYP6ER1 through injection of dsCYP6ER1 led to significant susceptibility in the NR strain. The current study expands our understanding of the nitenpyram resistance mechanism in N. lugens, provides an important reference for integrated pest management (IPM), and enriches the theoretical system of insect toxicology.
吡虫啉对褐飞虱（Nilaparvata lugens，BPH）非常有效，田间种群已报道其产生了抗性；然而，其抗性机制仍不清楚。本研究调查了吡虫啉抗性褐飞虱的交互抗性和抗性机制。通过连续 42 代从实验室敏感种群（NS）中选择，培育出具有高抗性水平（164.18 倍）的抗性种群（NR）。生物测定结果表明，NR 对吡虫啉（37.46 倍）、噻虫嗪（71.66 倍）、噻虫啉（149.17 倍）、噻虫胺（98.13 倍）、呋虫胺（47.24 倍）、环丙甲噻嗪（9.33 倍）、乙虫腈（10.51 倍）和异恶唑草酮（9.97 倍）表现出交互抗性，但对三氟甲吡醚、毒死蜱和噻嗪酮没有抗性。与 NS 相比，NR 细胞色素 P450 单加氧酶（P450）活性增加了 3.21 倍，同时与抑制剂增效醚（PBO）协同作用（4.03 倍），表明 P450 起作用。此外，定量实时 PCR 结果显示，十二种 P450 基因在 NR 株中显著过表达，特别是 CYP6ER1（203.22 倍）。通过注射 dsCYP6ER1 对 CYP6ER1 进行 RNA 干扰（RNAi）抑制导致 NR 株的敏感性显著增加。本研究扩展了我们对褐飞虱吡虫啉抗性机制的理解，为害虫综合治理（IPM）提供了重要参考，并丰富了昆虫毒理学理论体系。
