Rice, a vital crop, faces significant threats from the brown planthopper (BPH), which impacts plant growth and yield. Pyramiding the BPH resistance genes BPH14 and BPH15 provides rice crops with reliable and lasting protection against BPH. Nonetheless, current research lacks clarity on the molecular processes responsible for BPH14/BPH15-mediated resistance to BPH. In this study, utilizing high-throughput metabolomics and integrating transcriptomic data, we investigated the metabolic adaptations of the BPH14/BPH15 pyramiding line (B1415) and its recurrent parent (RP) during early and late infestation stages. The analysis identified 1007 metabolites, mainly consisting of lipids and lipid-like molecules, together with phenylpropanoid and polyketide classes. Differentially accumulated metabolites (DAMs) displayed different patterns in B1415 and RP, particularly in flavonoid and phenylpropanoid biosynthesis pathways, which were more pronounced in the resistant B1415. Furthermore, ferulic acid (FA) was found to negatively regulate BPH resistance. These findings elucidate critical metabolic pathways involved in rice defense mechanisms and underscore the potential of B1415’s enhanced metabolic responses in conferring durable resistance against BPH.

Rice farming faces a significant challenge from the brown planthopper (BPH), a destructive pest that threatens crop yields. Developing BPH-resistant rice v