Shi Pan, Guo Shao-Kun, Gao Yong-Fu, Cao Li-Jun, Gong Ya-Jun, Chen Jin-Cui, Yue Lei, Li Hu, Hoffmann Ary Anthony, Wei Shu-Jun
Institute of Plant and Environmental Protection Beijing Academy of Agriculture and Forestry Sciences Beijing China.
Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management College of Plant Protection China Agricultural University Beijing China.
Evol Appl. 2020 May 29;13(9):2234-2245. doi: 10.1111/eva.12996. eCollection 2020 Oct.
The melon thrips, , is an increasingly important pest of vegetables in northern China. Some populations have developed resistance in the field to the insecticide spinetoram. Understanding the origin and dispersal of insecticide-resistant populations can shed light on resistance management strategies. In this study, we tested susceptibility of seven greenhouse populations of to spinetoram collected from a small area of about 300 km in Shandong Province and examined population genetic structure across the area based on a segment of mitochondrial gene and 22 microsatellite loci to infer the possible origin and dispersal of insecticide resistance. Levels of resistance to spinetoram differed among seven populations, which included one population with high resistance (LC = 759.34 mg/L), three populations with medium resistance (LC ranged from 28.69 to 34.79 mg/L), and three populations with low resistance (LC ranged from 7.61 to 8.97 mg/L). The populations were genetically differentiated into two groups unrelated to both levels of resistance and geographic distance. The molecular data indicated high levels of gene flow between populations with different levels of resistance to spinetoram and low gene flow among populations with the same level of resistance, pointing to a likely separate history of resistance evolution. Resistance levels of two tested populations to spinetoram decreased 23 and 4.6 times after five generations without any exposure to the pesticide. We therefore suspect that resistance of most likely evolved in response to local applications of the insecticide. Our study suggests that the development of resistance could be avoided or resistance even reversed by reducing usage of spinetoram.
西花蓟马是中国北方蔬菜上一种日益重要的害虫。一些种群已在田间对杀虫剂多杀霉素产生了抗性。了解抗药性种群的起源和扩散有助于制定抗性管理策略。在本研究中，我们测试了从山东省约300平方公里的小区域采集的7个温室西花蓟马种群对多杀霉素的敏感性，并基于线粒体基因片段和22个微卫星位点检测了该区域的种群遗传结构，以推断抗药性的可能起源和扩散情况。7个种群对多杀霉素的抗性水平不同，其中一个种群具有高抗性（LC₅₀ = 759.34 mg/L），三个种群具有中等抗性（LC₅₀范围为28.69至34.79 mg/L），三个种群具有低抗性（LC₅₀范围为7.61至8.97 mg/L）。这些种群在遗传上分为两组，与抗性水平和地理距离均无关。分子数据表明，对多杀霉素抗性水平不同的种群之间基因流水平较高，而抗性水平相同的种群之间基因流水平较低，这表明抗性进化可能有不同的历史。两个受试种群在五代未接触任何杀虫剂后，对多杀霉素的抗性水平分别下降了23倍和四倍半。因此，我们怀疑西花蓟马的抗性很可能是对当地使用该杀虫剂的反应而进化产生的。我们的研究表明，通过减少多杀霉素的使用，可以避免抗性的发展，甚至可能逆转抗性。
