Abstract
Anthracnose disease caused by Colletotrichum fructicola severely compromises the medicinal value and yield of Dendrobium officinale. To elucidate the host metabolic response to pathogen infection, we integrated transcriptomic and metabolomic analyses of D. officinale challenged with C. fructicola. Our results revealed a profound metabolic reprogramming orchestrated by the pathogen, characterized by upregulated flavonoid biosynthesis (e.g., DFR, LDOX activation) and enhanced lipid catabolism (e.g., β-oxidation via LACS, DECR, HACL). Metabolite profiling demonstrated a significant reduction in phosphatidylcholine (PC) and phosphatidylethanolamine (PE) alongside increased free fatty acids, indicating active lipid degradation. Notably, acyl-CoA intermediates linked lipid catabolism to flavonoid production, suggesting a metabolic axis where pathogen-induced lipid breakdown fuels defense-related secondary metabolite synthesis. This study identifies flavonoid and lipid metabolic reprogramming as critical axes in host-pathogen interactions, providing a foundation for developing targeted disease control strategies.