Metabolomic Analysis Identifies Synergistic Role of Hormones Biosynthesis and Phenylpropenoid Pathways during Fusarium Wilt Resistance in Tomato Plants

Fungal wilt diseases are among the most destructive pathogens attacking crop plants globally. Host resistance is considered a key for Fusarium wilt management. Some resistant plant varieties have been screened, but the underlying mechanisms are poorly understood. Here detailed metabolomic analysis was performed of resistant and susceptible tomato varieties in response to Fusarium wilt infection. A total of 73 metabolites were identified in the resistant and susceptible tomato plant samples. Functional categorization of these differentially produced metabolites indicated extensive re-modulations in plant physiology. Perception of F. oxysporum caused activation of signaling pathways and over production of some precursor molecules in different carbon cycles. These precursor metabolites were mainly channeled into hormones biosynthesis, phenylpropenoid and alkaloid biosynthesis pathways. This all together produced significantly higher quantities of different defense factors such as phenolics, terpenoids and alkaloids in resistant tomato variety upon pathogen attack. This up-regulation of defense-related metabolism contributed to resistance against Fusarium wilt disease in tomato plants. These results improve our understanding about underlying mechanisms and identify metabolites and pathways related to specific resistance mechanisms. Current study suggests that, in contrast to previous knowledge, there exists a synergistic effect between hormone biosynthesis and phenylpropenoid pathway in resistance reaction against Fusarium wilt disease. This knowledge can help to improve the durability of resistance against Fusarium wilt disease. © 2017 Friends Science Publishers