Effects of Trehalose-6-Phosphate Synthase on the Reproduction and Development of Nilaparvata lugens and Its Molecular Mechanism

<i>Nilaparvata lugens</i> is a migratory pest with high fecundity and outstanding drug resistance, which poses a devastating danger to rice production. This study investigated the reproductive regulation mechanism of <i>N. lugens</i>, specifically silencing the trehalose-6-phosphate synthase gene (<i>TPS</i>) via RNAi to elucidate how <i>TPS</i> governs the trehalose metabolic network through modulation of trehalose biosynthesis. Insect fecundity hinges on the synchronized progression of oogenesis and the tightly controlled expression of vitellogenin (Vg). In <i>N. lugens</i>, this coordination is orchestrated by an integrated molecular network that converges juvenile hormone signaling (JH), 20-hydroxyecdysone pathways (20E), insulin/IGF signaling (IIS), and the target of rapamycin cascade (TOR), collectively dictating the reproductive output of the species. Using <i>TPS</i> knockdown as the entry point, this study dissects the lipid-metabolic circuitry of <i>N. lugens</i> and uncovers how hormonal signaling cascades orchestrate reproduction by precisely modulating vitellogenin (Vg) and its cognate receptor VgR. Synthesized double-stranded terpene synthase genes (dsTPSs) can degrade mRNA, inhibit protein translation, and ultimately lead to the silencing of <i>TPS</i> genes, simultaneously crippling energy provision and hormonal signaling to orchestrate a multi-pronged suppression of reproduction. This dual-action intervention offers a promising molecular target for environmentally friendly management of <i>N. lugens</i>.