Yang Yuanxue, Huang Lixin, Wang Yunchao, Zhang Yixi, Fang Siqi, Liu Zewen
Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China.
Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China.
Pestic Biochem Physiol. 2016 Jun;130:79-83. doi: 10.1016/j.pestbp.2015.11.007. Epub 2015 Nov 26.
Cross-resistance between insecticides, especially from different groups, can be extremely unpredictable, and it has been a serious concern in pest control. Pymetrozine has been widely used to control Nilaparvata lugens with the suspension of imidacloprid for the resistance, and N. lugens has showed obvious pymetrozine resistance in recent years. To investigate the possible cross-resistance between imidacloprid and pymetrozine is very important to avoid the adverse effects on resistance development and pest control. Bioassays of two field populations in five consecutive years showed that imidacloprid resistance decreased greatly, while pymetrozine resistance increased significantly. The synergist piperonyl butoxide (PBO) could synergize both imidacloprid and pymetrozine in all field populations, which indicated the importance of P450s in the resistance to two insecticides. Imidacloprid resistance was reported to be associated with two P450s, CYP6AY1 and CYP6ER1, which could metabolize imidacloprid efficiently. However, the recombinant proteins of these two P450s did not show any enzymatic activity to metabolize pymetrozine. The pymetrozine susceptibility did not change when CYP6AY1 and CYP6ER1 mRNA levels were reduced by RNA interference (RNAi), although which could obviously decrease imidacloprid resistance. In vivo and in vitro studies provided evidences to demonstrate that there was no cross-resistance between imidacloprid and pymetrozine in N. lugens, which was different from the findings in Bemisia tabaci.
杀虫剂之间的交互抗性，尤其是来自不同类别的杀虫剂之间的交互抗性，可能极其难以预测，并且一直是害虫防治中的一个严重问题。由于褐飞虱对吡虫啉产生了抗性，吡蚜酮已被广泛用于防治褐飞虱，并且近年来褐飞虱对吡蚜酮已表现出明显的抗性。研究吡虫啉与吡蚜酮之间可能存在的交互抗性对于避免对抗性发展和害虫防治产生不利影响非常重要。对两个田间种群连续五年进行的生物测定表明，褐飞虱对吡虫啉的抗性大幅下降，而对吡蚜酮的抗性则显著增加。增效剂胡椒基丁醚（PBO）在所有田间种群中对吡虫啉和吡蚜酮均有增效作用，这表明细胞色素P450在对这两种杀虫剂的抗性中具有重要作用。据报道，褐飞虱对吡虫啉的抗性与两种细胞色素P450，即CYP6AY1和CYP6ER1有关，它们能够高效代谢吡虫啉。然而，这两种细胞色素P450的重组蛋白对吡蚜酮均未表现出任何代谢酶活性。当通过RNA干扰（RNAi）降低CYP6AY1和CYP6ER1的mRNA水平时，褐飞虱对吡蚜酮的敏感性并未改变，尽管这可以明显降低其对吡虫啉的抗性。体内和体外研究均提供了证据，证明褐飞虱对吡虫啉和吡蚜酮不存在交互抗性，这与在烟粉虱中的研究结果不同。
