Key Laboratory of Integrated Management of Crop Diseases and Pests (Ministry of Education), College of Plant Protection, Nanjing Agricultural University, Nanjing, China.
School of Pharmacy, East China University of Science and Technology, Shanghai, China.
Pest Manag Sci. 2018 Jan;74(1):234-239. doi: 10.1002/ps.4705. Epub 2017 Sep 26.
Fitness costs associated with insecticide resistance in pest insects have mainly been studied under optimal laboratory conditions. However, resistant insects face more stressors than just insecticides in the field, and how the resistant population reacts to these stressors is of practical importance for the control of pest insects such as the brown planthopper Nilaparvata lugens. The aim of the present study was to explore the impact of population density on the competitiveness of resistant and susceptible individuals.
Two isogenic N. lugens populations, a highly imidacloprid-resistant population (HZ-R) with a resistance ratio (RR) of 227.10 and a relatively susceptible population (HZ-S) with an RR of 2.99, were created from a field-resistant population (HZ; RR 62.51). The high resistance levels of HZ-R and HZ were mainly attributable to the overexpression of multiple cytochrome P450 (CYP) genes such as CYP6ER1, CYP6AY1, CYP6CW1 and CYP4CE1 compared with HZ-S, this being supported by piperonyl butoxide synergism. HZ-R was observed to be more resistant to thiacloprid and etofenprox compared with HZ and HZ-S. Most interestingly, in high population density treatments, HZ-S individuals were much more competitive than HZ-R individuals.
Imidacloprid-resistant individuals of N. lugens are less competitive than their susceptible counterparts under density pressure. © 2017 Society of Chemical Industry.
与害虫杀虫剂抗性相关的适应成本主要在最佳实验室条件下进行了研究。然而，抗性昆虫在野外面临的压力不仅仅是杀虫剂，了解抗性种群对这些压力的反应对于害虫（如褐飞虱 Nilaparvata lugens）的控制具有实际意义。本研究旨在探讨种群密度对抗性和敏感个体竞争力的影响。
从田间抗性种群（HZ；RR62.51）中创建了两个具有相同遗传背景的褐飞虱种群，一个高度氯吡虫啉抗性种群（HZ-R，RR227.10）和一个相对敏感种群（HZ-S，RR2.99）。与 HZ-S 相比，HZ-R 和 HZ 的高抗性水平主要归因于多种细胞色素 P450（CYP）基因的过度表达，如 CYP6ER1、CYP6AY1、CYP6CW1 和 CYP4CE1，这得到了增效醚协同作用的支持。与 HZ 和 HZ-S 相比，HZ-R 对噻虫啉和乙氧呋草黄的抗性更强。最有趣的是，在高密度处理中，HZ-S 个体比 HZ-R 个体更具竞争力。
褐飞虱对吡虫啉的抗性个体在密度压力下比敏感个体的竞争力低。 © 2017 化学工业协会。
