Teng Haiyuan, Zuo Yayun, Yuan Jing, Fabrick Jeffrey A, Wu Yidong, Yang Yihua
College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Institute of Eco-Environmental and Plant Protection, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China.
College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; Institute of Pesticide Science, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China.
Pestic Biochem Physiol. 2022 Aug;186:105153. doi: 10.1016/j.pestbp.2022.105153. Epub 2022 Jun 24.
The beet armyworm, Spodoptera exigua is a global agricultural pest that is polyphagous, highly dispersive, and often difficult to control due to resistance to many insecticides. Previous studies showed that a target site mutation in the S. exigua ryanodine receptor (SeRyR) corresponding to I4743M contributes approximately 20-fold resistance to chlorantraniliprole, whereas a mutation in the cytochrome P450 enzyme CYP9A186 corresponding to F116V confers 200-fold to emamectin benzoate through enhanced metabolic detoxification. Here, high frequencies of mutations were found among six China S. exigua field populations collected from 2016 to 2019 resulting in SeRyR I4743M and CYP9A186 F116V substitutions, with some populations having high levels of resistance to chlorantraniliprole and emamectin benzoate, respectively. Whereas we found a significant correlation between emamectin benzoate resistance level and the allele frequency of CYP9A186 F116V, no significant correlation was found between chlorantraniliprole resistance level and SeRyR I4743M allele frequency in the six field populations. These results suggest that CYP9A186 F116V is a major resistance mechanism for emamectin benzoate in the tested field populations, whereas it is likely that resistance mechanisms other than SeRyR I4743M are responsible for resistance to chlorantraniliprole in the six China field populations. Because of the growing resistance to these two insecticides by S. exigua in China, the use of insecticidal compounds with different modes of action and/or other integrated pest management strategies are needed to further delay the evolution of insecticide resistance and effectively manage S. exigua in China.
甜菜夜蛾（Spodoptera exigua）是一种全球性农业害虫，食性广泛，极具扩散性，且由于对多种杀虫剂产生抗性，常常难以防治。先前的研究表明，甜菜夜蛾兰尼碱受体（SeRyR）中对应于I4743M的一个靶位点突变使甜菜夜蛾对氯虫苯甲酰胺产生约20倍的抗性，而细胞色素P450酶CYP9A186中对应于F116V的一个突变通过增强代谢解毒作用使甜菜夜蛾对甲氨基阿维菌素苯甲酸盐产生200倍的抗性。在此，在2016年至2019年采集的6个中国甜菜夜蛾田间种群中发现了高频率的突变，导致SeRyR I4743M和CYP9A186 F116V替换，一些种群分别对氯虫苯甲酰胺和甲氨基阿维菌素苯甲酸盐具有高水平抗性。虽然我们发现甲氨基阿维菌素苯甲酸盐抗性水平与CYP9A186 F116V的等位基因频率之间存在显著相关性，但在这6个田间种群中，氯虫苯甲酰胺抗性水平与SeRyR I4743M等位基因频率之间未发现显著相关性。这些结果表明，CYP9A186 F116V是受试田间种群中甲氨基阿维菌素苯甲酸盐的主要抗性机制，而在中国的这6个田间种群中，除SeRyR I4743M之外的其他抗性机制可能是导致对氯虫苯甲酰胺产生抗性的原因。由于在中国甜菜夜蛾对这两种杀虫剂的抗性不断增强，需要使用具有不同作用方式的杀虫化合物和/或其他综合害虫管理策略，以进一步延缓抗药性的发展并有效治理中国的甜菜夜蛾。
