Department of Plant Biosecurity and MARA Key Laboratory of Surveillance and Management for Plant Quarantine Pests, College of Plant Protection, China Agricultural University, Beijing 100193, China.
Int J Mol Sci. 2022 Aug 20;23(16):9388. doi: 10.3390/ijms23169388.
Sublethal doses of insecticides have many impacts on pest control and agroecosystems. Insects that survive a sublethal dose of insecticide could adapt their physiological and behavioral functions and resist this environmental stress, which contributes to the challenge of pest management. In this study, the sublethal effects of thiamethoxam on gene expression were measured through RNA sequencing in the melon aphid . Genes regulating energy production were downregulated, while genes related to neural function were upregulated. To further address the function of genes related to neurotransmission, RNA interference (RNAi) was implemented by transdermal delivery of dsRNA targeting (), a gene regulating presynaptic vesicle clustering. The gene expression of was knocked down and the mortality of aphids was increased significantly over the duration of the assay. Co-delivery of syn-dsRNA and thiamethoxam reversed the upregulation of caused by low-dose thiamethoxam and resulted in lethality to melon aphids, suggesting that the decreased presynaptic function may contribute to this synergistic lethal effect. In addition, the nanocarrier star polycation, which could bind both dsRNA and thiamethoxam, greatly improved the efficacy of lethality. These results increase our knowledge of the gene regulation induced by sublethal exposure to neonicotinoids and indicated that could be a potential RNAi target for resistance management of the melon aphid.
亚致死剂量的杀虫剂对害虫防治和农业生态系统有许多影响。昆虫在亚致死剂量的杀虫剂中幸存下来后，可能会调整其生理和行为功能，抵抗这种环境压力，这给害虫管理带来了挑战。在这项研究中，通过对瓜蚜的 RNA 测序，测量了噻虫嗪对基因表达的亚致死效应。调节能量产生的基因下调，而与神经功能相关的基因上调。为了进一步研究与神经递质传递相关的基因的功能，通过透皮递送靶向调节突触前囊泡聚集的基因 () 的 dsRNA 进行 RNA 干扰 (RNAi)。的基因表达被敲低，并且在整个测定期间蚜虫的死亡率显著增加。与低剂量噻虫嗪共同递送 syn-dsRNA 和噻虫嗪逆转了低剂量噻虫嗪引起的上调，并导致瓜蚜死亡，表明突触前功能的降低可能导致这种协同致死作用。此外，纳米载体星型聚阳离子可以结合 dsRNA 和噻虫嗪，大大提高了致死效果。这些结果增加了我们对亚致死接触新烟碱类杀虫剂诱导的基因调控的认识，并表明可能是瓜蚜抗性管理的潜在 RNAi 靶标。
