Yainna Sudeeptha, Nègre Nicolas, Silvie Pierre J, Brévault Thierry, Tay Wee Tek, Gordon Karl, dAlençon Emmanuelle, Walsh Thomas, Nam Kiwoong
DGIMI, University of Montpellier, INRAE, F-34095 Montpellier, France.
CIRAD, UPR AIDA, F-34398 Montpellier, France.
Insects. 2021 May 18;12(5):468. doi: 10.3390/insects12050468.
Field evolved resistance to insecticides is one of the main challenges in pest control. The fall armyworm (FAW) is a lepidopteran pest species causing severe crop losses, especially corn. While native to the Americas, the presence of FAW was confirmed in West Africa in 2016. Since then, the FAW has been detected in over 70 countries covering sub-Saharan Africa, the Middle East, North Africa, South Asia, Southeast Asia, and Oceania. In this study, we tested whether this invasion was accompanied by the spread of resistance mutations from native to invasive areas. We observed that mutations causing Bt resistance at ABCC2 genes were observed only in native populations where the mutations were initially reported. Invasive populations were found to have higher gene numbers of cytochrome P450 genes than native populations and a higher proportion of multiple resistance mutations at acetylcholinesterase genes, supporting strong selective pressure for resistance against synthetic insecticides. This result explains the susceptibility to Bt insecticides and resistance to various synthetic insecticides in Chinese populations. These results highlight the necessity of regular and standardized monitoring of insecticide resistance in invasive populations using both genomic approaches and bioassay experiments.
田间对杀虫剂产生的抗性是害虫防治中的主要挑战之一。草地贪夜蛾是一种鳞翅目害虫，会造成严重的作物损失，尤其是玉米。草地贪夜蛾原产于美洲，2016年在西非被确认存在。从那时起，在撒哈拉以南非洲、中东、北非、南亚、东南亚和大洋洲的70多个国家都检测到了草地贪夜蛾。在本研究中，我们测试了这种入侵是否伴随着抗性突变从原生区域向入侵区域的传播。我们观察到，仅在最初报告这些突变的原生种群中发现了导致ABCC2基因对Bt产生抗性的突变。发现入侵种群的细胞色素P450基因数量比原生种群多，并且乙酰胆碱酯酶基因上多重抗性突变的比例更高，这支持了对合成杀虫剂抗性的强大选择压力。这一结果解释了中国种群对Bt杀虫剂的敏感性以及对各种合成杀虫剂的抗性。这些结果凸显了使用基因组方法和生物测定实验对入侵种群的杀虫剂抗性进行定期和标准化监测的必要性。
