The fall armyworm, Spodoptera frugiperda, has developed extremely high levels of resistance to chlorantraniliprole and other classes of insecticides in the field. As microRNAs (miRNAs) play important roles in various biological processes through gene regulation. we examined the miRNA profile of S. frugiperda in response to Chlorantraniliprole, Indoxacarb and Thiamethoxam. Transcriptome analysis showed significant changes in the abundance of some miRNAs after treatment of S. frugiperda larvae with LC20 concentrations of three insecticides. A total of 197 miRNAs were systematically identified from S. frugiperda, and 16, 9, 2 miRNAs were differentially expressed after treatments of three insecticides. Importantly, three miRNAs were significantly downregulated and three were upregulated by RT-qPCR after treatment the LC50 of three insecticides with S. frugiperda larvae. Microinjection of agomirs of these six miRNAs into S. frugiperda larvae resulted in significant changes in mortality rates when exposed to three insecticides. Additionally, we also screened potential target genes for some of differentially expressed miRNAs, which may play important roles in insecticide resistance development. These findings provide valuable insights into the molecular mechanisms of insecticide resistance and underscore the potential of miRNAs as targets for the development of novel pest control strategies in S. frugiperda.

배추좀나방의 발육단계별 indoxacarb의 살충활성, 침투이행성 및 잔효성을 조사하였고, esterase, acetylcholinesterase, glutathione S-transferase 등의 효소활성에 미치는 영향을 검토하였다. 배추좀나방 유충에 대해서 높은 살충효과를 나타내었으나, 알과 번데기에 대해서는 살충율이 이하이었다. 엽면침투이행성과 근부침투이행성의 효과는 없었으며, 잔효성은 10일째까지 의 살충효과를 유지하였다. Indoxacarb는 esterase와 glutathione S-transferase의 활성은 저해하지 않았지만 acetylcholinesterase의 활성을 저해하였다.