Gao Tian, Zhang Yong, Sun Wanpeng, Li Qiangkun, Huang Xueyu, Zhi Dian, Zi Huabin, Ji Ruijie, Long Yanhua, Gong Chunmei, Yang Yunqiu
State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China; College of Horticulture, Northwest A＆F University, Yangling, Shaanxi, China.
State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, Hefei, China.
Ecotoxicol Environ Saf. 2025 Jan 1;289:117666. doi: 10.1016/j.ecoenv.2025.117666. Epub 2025 Jan 3.
The global issue of insecticide resistance among pests is a major concern. Ectropis grisescens Warren (Lepidoptera: Geometridae), is a highly destructive leaf-eating pest distributed in tea plantations throughout China and Japan, and has exhibited resistance to various insecticides. Recent studies suggest that insect symbionts play a role in influencing insecticide resistance, however, their specific involvement in E. grisescens remains unclear. Here, we initially selected appropriate antibiotic mixtures at a concentration of 300 μg ml. The bioassay results showed that the insecticide susceptibility of the E. grisescens population treated with antibiotic mixtures significantly increased exposed to bifenthrin. Comparative analysis revealed that the LC value, survival rate, P450 enzyme activity, and relative content of Wolbachia in the E. grisescens population treated with 300 μg ml tetracycline were notably lower than those treated with other antibiotics (ampicillin, gentamicin, and streptomycin). Moreover, the population treated with 2.5 mg ml tetracycline exhibited even greater reductions in these parameters than the 300 μg ml tetracycline-treated group. Additionally, 16S rRNA sequencing results showed a significant decrease in xenobiotics metabolism by cytochrome P450 in the E. grisescens population treated with 2.5 mg ml tetracycline. Transcriptome analysis showed a significant down-regulation of two cytochrome P450 genes in E. grisescens population without Wolbachia. These results suggest that Wolbachia may contribute to the resistance of E. grisescens to bifenthrin by regulating cytochrome P450 genes, providing a foundation for further study on the mechanism of symbiont-mediated host detoxification metabolism in insect pests.
害虫对杀虫剂产生抗性这一全球性问题令人深感忧虑。茶尺蠖（Ectropis grisescens Warren，鳞翅目：尺蛾科）是一种极具破坏性的食叶害虫，分布于中国和日本的茶园，且已对多种杀虫剂表现出抗性。近期研究表明昆虫共生菌在影响杀虫剂抗性方面发挥作用，然而，它们在茶尺蠖中的具体作用仍不明确。在此，我们首先选择了浓度为300μg/ml的合适抗生素混合物。生物测定结果显示，经抗生素混合物处理的茶尺蠖种群在接触联苯菊酯后，其对杀虫剂的敏感性显著提高。比较分析表明，用300μg/ml四环素处理的茶尺蠖种群的LC值、存活率、P450酶活性和沃尔巴克氏体相对含量明显低于用其他抗生素（氨苄青霉素、庆大霉素和链霉素）处理的种群。此外，用2.5mg/ml四环素处理的种群在这些参数上的降低幅度甚至比300μg/ml四环素处理组更大。另外，16S rRNA测序结果表明，用2.5mg/ml四环素处理的茶尺蠖种群中细胞色素P450对外源化合物的代谢显著减少。转录组分析显示，在没有沃尔巴克氏体的茶尺蠖种群中，两个细胞色素P450基因显著下调。这些结果表明，沃尔巴克氏体可能通过调节细胞色素P450基因来促使茶尺蠖对联苯菊酯产生抗性，为进一步研究共生菌介导的害虫宿主解毒代谢机制奠定了基础。
