Biocidal function of Trichoderma-derived secondary metabolites against Fusarium wilt of pea

The current research investigates the potential of secondary metabolites extracted from Trichoderma species for managing Fusarium wilt in pea plants. Crude extracts of secondary metabolites from T. viride and T. harzianum were obtained using ethyl acetate and methanol through solvent extraction methods and evaluated for their antifungal activity against Fusarium oxysporum f.sp. pisi under various experimental conditions. In vitro assays were performed using the poisoned food technique on potato dextrose agar (PDA) medium, employing Completely Randomized Design (CRD) with three concentrations of secondary metabolites (250 ppm, 350 ppm, and 500 ppm). Greenhouse experiments were also conducted in a CRD setup, where pea plants were inoculated with a spore suspension (1×10⁶ spores/ml) of the pathogen and treated with different concentrations of metabolites through soil drenching. For field trials, a Randomized Complete Block Design was utilized to evaluate the most effective concentration (500 ppm) of metabolites, applied via hand sprayer and soil drenching. Results showed that the combination of T. viride and T. harzianum metabolites significantly reduced mycelial growth (10.11 mm) under laboratory conditions and decreased disease incidence to 27.08% in greenhouse trials and 28.15% in field trials. These findings highlight the potential of Trichoderma-derived secondary metabolites as a sustainable approach for managing Fusarium wilt in pea plants, offering promising prospects for integrated disease management strategies.