NPF and sNPF can regulate lipid metabolism to prevent oxidative imbalance in the brown planthopper under elevated CO 2

BACKGROUND Elevated atmospheric carbon dioxide (eCO 2 ) exacerbates feeding damage of the destructive rice pest brown planthopper ( Nilaparvata lugens ). Neuropeptide F (NPF) and short Neuropeptide F (sNPF) are core regulators of insect feeding and metabolism, yet their functions in mediating N. lugens responses to eCO 2 remain unclear. This study aimed to elucidate the roles of NPF and sNPF in modulating the feeding behavior, lipid metabolism and oxidative balance of N. lugens under eCO 2 . RESULTS NPF / sNPF knockdown prolonged N. lugens feeding duration, with more prominent effects under eCO 2 than ambient CO 2 . Silencing the two genes enriched differential expression genes in ‘fat digestion and absorption’ pathways, and it significantly elevated triglyceride and free fatty acid contents, reduced the ratio of polyunsaturated to saturated fatty acids, and triggered higher reactive oxygen species and malondialdehyde levels with weakened antioxidant capacity, ultimately increasing pest mortality. Dual gene knockdown exerted stronger impacts than single knockdown, and all phenotypic changes were amplified under eCO 2 . CONCLUSION NPF and sNPF coordinately regulate the feeding, lipid homeostasis and oxidative balance of N. lugens under eCO 2 . The close correlation of their regulatory effects with lipid metabolism and oxidative stress clarifies the molecular mechanism of pest climate adaptation. This work advances climate‐related pest resistance research and provides promising molecular targets for brown planthopper biocontrol.