Institute of Plant and Environmental Protection, Beijing Academy of Agricultural and Forestry Sciences, Haidian District, Beijing, China.
Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China.
J Econ Entomol. 2021 Feb 9;114(1):339-347. doi: 10.1093/jee/toaa314.
Putative mechanisms underlying spinosyn resistance have been identified in controlled studies on many species; however, mechanisms underlying field-evolved resistance and the development of a molecular diagnostic method for monitoring field resistance have lagged behind. Here, we examined levels of resistance of melon thrips, Thrips palmi Karny (Thysanoptera:Thripidae), to spinetoram as well as target site mutations in field populations across China to identify potential mechanisms and useful molecular markers for diagnostic and quantifying purposes. In resistant populations, we identified the G275E mutation, which has previously been linked to spinosyns resistance, and F314V mutation, both located in the α6 subunit of the nicotinic acetylcholine receptor. There was a strong correlation between levels of spinetoram resistance and allele frequency of G275E mutation in field-collected populations (r2 = 0.84) and those reared under laboratory conditions for two to five generations (r2 = 0.91). LC50 ranged from 0.12 to 0.66 mg/liter in populations without G275E mutation, whereas it ranged from 33.12 to 39.91 mg/liter in most populations with a G275E mutation frequency more than 90%. Our results indicate that the field-evolved resistance of T. palmi to spinetoram in China is mainly conferred by the G275E mutation. The frequency of the G275E mutation provides a useful diagnostic for quantifying resistance levels in field populations of T. palmi.
在许多物种的对照研究中已经确定了吡虫啉抗性的潜在机制；然而，田间进化抗性的机制以及用于监测田间抗性的分子诊断方法的发展却滞后了。在这里，我们研究了瓜蓟马，蓟马 palmi Karny（缨翅目：蓟马科）对 spinetoram 的抗性水平以及中国各地田间种群的靶标部位突变，以确定潜在的机制和有用的分子标记，用于诊断和定量目的。在抗性种群中，我们发现了以前与吡虫啉抗性相关的 G275E 突变和 F314V 突变，这两种突变都位于烟碱型乙酰胆碱受体的α6 亚基上。在田间采集的种群中，spinetoram 抗性水平与 G275E 突变等位基因频率之间存在很强的相关性（r2 = 0.84），在实验室条件下连续两代到五代饲养的种群中也存在很强的相关性（r2 = 0.91）。在没有 G275E 突变的种群中，LC50 范围为 0.12 至 0.66 毫克/升，而在大多数 G275E 突变频率超过 90%的种群中，LC50 范围为 33.12 至 39.91 毫克/升。我们的结果表明，中国瓜蓟马对 spinetoram 的田间进化抗性主要由 G275E 突变赋予。G275E 突变的频率为定量测定田间种群的抗性水平提供了有用的诊断方法。
