AUTHOR=Li Chunxia , Nie Jiahui , Wu Xingbiao , Zhang Yuting , Li Xiang , Wu Xia , Yin Kuide , Jin Yazhong 

TITLE=Oriental melon roots metabolites changing response to the pathogen of Fusarium oxysporum f. sp. melonis mediated by Trichoderma harzianum

JOURNAL=Frontiers in Sustainable Food Systems

VOLUME=8

YEAR=2024

URL=https://www.frontiersin.org/journals/sustainable-food-systems/articles/10.3389/fsufs.2024.1354468

DOI=10.3389/fsufs.2024.1354468

ISSN=2571-581X

ABSTRACT=<sec><title>Introduction</title><p><italic>Trichoderma</italic> spp. is a recognized bio-control agent that promotes plant growth and enhances resistance against soil-borne diseases, especially <italic>Fusarium</italic> wilt. It is frequently suggested that there is a relationship between resistance to melon wilt and changes in soil microbiome structures in the rhizosphere with plant metabolites. However, the exact mechanism remains unclear.</p></sec><sec><title>Method</title><p>This study aims to investigate the effects of <italic>Trichoderma</italic> application on the metabolic pathway of oriental melon roots in response to <italic>Fusarium oxysporum</italic> f. sp. <italic>melonis</italic> in a pot experiment. The experiment consisted of three treatments, namely water-treated (CK), <italic>FOM</italic>-inoculated (KW), and <italic>Trichoderma</italic>-applied (MM) treatments, that lasted for 25 days. Ultra-performance liquid chromatography-electron spray ionization-mass spectrometry (UPLC-ESI-MS) was used to analyze the compounds in melon roots.</p></sec><sec><title>Results</title><p>The results show that <italic>Trichoderma harzianum</italic> application resulted in a reduction in the severity of oriental melon <italic>Fusarium</italic> wilt. A total of 416 distinct metabolites, categorized into four groups, were detected among the 886 metabolites analyzed. Additionally, seven differential metabolites were identified as key compounds being accumulated after inoculation with <italic>Fusarium oxysporum</italic> f. sp. <italic>melonis</italic> (<italic>FOM</italic>) and <italic>Trichoderma</italic>. The mechanism by which <italic>Trichoderma</italic> enhanced melon's resistance to <italic>Fusarium</italic> wilt was primarily associated with glycolysis/gluconeogenesis, phenylpropanoid biosynthesis, flavone and flavonol biosynthesis, and the biosynthesis of cofactors pathway. In comparison with the treatments of CK and MM, the KW treatment increased the metabolites of flavone and flavonol biosynthesis, suggesting that oriental melon defended against pathogen infection by increasing flavonol biosynthesis in the KW treatment, whereas the application of <italic>Trichoderma harzianum</italic> decreased pathogen infection while also increasing the biosynthesis of glycolysis/gluconeogenesis and biosynthesis of cofactors pathway, which were related to growth. This study also aims to enhance our understanding of how melon responds to <italic>FOM</italic> infection and the mechanisms by which <italic>Trichoderma harzianum</italic> treatment improves melon resistance at the metabolic level.</p></sec>