Table1_Potential inhibitory effects of compounds ZK-PI-5 and ZK-PI-9 on trehalose and chitin metabolism in Spodoptera frugiperda (J. E. Smith).DOCX

Introduction:Spodoptera frugiperda is an omnivorous agricultural pest which is great dangerous for grain output.
Methods: In order to investigate the effects of potential trehalase inhibitors, ZK-PI-5 and ZK-PI-9, on the growth and development of S. frugiperda, and to identify new avenues for S. frugiperda control, we measured the content of the trehalose, glucose, glycogen and chitin, enzyme activity, and gene expression levels in trehalose and chitin metabolism of S. frugiperda. Besides, their growth and development were also observed.
Results: The results showed that ZK-PI-9 significantly reduced trehalase activity and ZK-PI-5 significantly reduced membraned-bound trehalase activity. Moreover, ZK-PI-5 inhibited the expression of SfTRE2, SfCHS2, and SfCHT, thus affecting the chitin metabolism. In addition, the mortality of S. frugiperda in pupal stage and eclosion stage increased significantly after treatment with ZK-PI-5 and ZK-PI-9, which affected their development stage and caused death phenotype (abnormal pupation and difficulty in breaking pupa).
Discussion: These results have provided a theoretical basis for the application of trehalase inhibitors in the control of agricultural pests to promote future global grain yield.

引言：草地贪夜蛾（Spodoptera frugiperda）是一种杂食性农业害虫，对粮食产量构成严重威胁。方法：为探究潜在海藻糖酶（trehalase）抑制剂ZK-PI-5与ZK-PI-9对草地贪夜蛾生长发育的影响，并为该害虫的防治探寻新途径，本研究测定了草地贪夜蛾体内海藻糖（trehalose）、葡萄糖、糖原（glycogen）与几丁质（chitin）的含量，以及海藻糖与几丁质代谢相关的酶活性及基因表达水平；同时对其生长发育状况进行了系统观察。结果：研究结果表明，ZK-PI-9可显著降低总海藻糖酶活性，而ZK-PI-5可显著抑制膜结合型海藻糖酶活性。此外，ZK-PI-5能够下调SfTRE2、SfCHS2及SfCHT的基因表达，进而干扰几丁质代谢通路。经ZK-PI-5与ZK-PI-9处理后，草地贪夜蛾的蛹期与羽化期死亡率显著升高，这扰乱了其正常发育进程并引发致死表型（化蛹异常、破蛹困难）。讨论：本研究结果为海藻糖酶抑制剂应用于农业害虫防治提供了坚实的理论依据，有助于提升未来全球粮食总产量。