Biocontrol of Fungal Pathogens of Capsicum annuum L. by Trichoderma Spp.

Antagonistic effectiveness of three Trichoderma species (T. harzianum, T. viride, and T. asperellum) against capsicum pathogens (Fusarium oxysporum, Colletotrichum capsici, Alternaria alternata, and Rhizoctonia solani.) was assessed using dual culture assays, volatile and non-volatile metabolite evaluations, and microscopic interaction studies. Trichoderma harzianum demonstrated highest inhibitory activity, recording 82 % suppression of radial growth. Mechanisms of antagonism included mycoparasitism, hyphal coiling, competition for nutrients and space, and production of antifungal metabolites. Microscopic observations confirmed extensive lytic zones and frequent penetration events. These findings confirmed strong bio-control potential of Trichoderma spp.