A novel endophytic Penicillium sp. JL76001 and its metabolite sclerotiorin: A multi-target and sustainable strategy for biocontrol of tomato Fusarium wilt.

Tomato Fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici (FOL), is a devastating disease that leads to yield losses of up to 67% in severely affected regions. Current control strategies, such as chemical treatments and resistant cultivars, face challenges including environmental toxicity and pathogen resistance. In this study, we isolated an endophytic fungus, Penicillium sp. JL76001 (JL76001), from the medicinal plant Asarum forbesii, which exhibited strong antagonism against FOL. Plate confrontation assays revealed a 40.48% inhibition of FOL growth, attributed to the secondary metabolite sclerotiorin (SCL). The minimum inhibitory concentration (MIC) of SCL against FOL was determined to be 12.5 μg/mL. Microscopic observations revealed severe hyphal distortion and ultrastructural damage in the fungal cells. Proteomic analysis identified 354 differentially expressed proteins in FOL under SCL treatment, which disrupted cysteine metabolism, oxidative phosphorylation, and cell membrane integrity. In simulated field trials, the crude metabolite extract (CME) of JL76001 achieved a control efficacy of 55.17% against tomato Fusarium wilt. Furthermore, JL76001 demonstrated the capability to produce SCL using agricultural waste residues, suggesting a sustainable strategy for waste valorization. Our study presents JL76001 and SCL as promising biocontrol agents for the sustainable management of tomato Fusarium wilt.