Evaluation of Antagonistic Activity of Trichoderma Spp. For Sustainable Management of Plant Diseases

Plant diseases caused by soil-borne phytopathogenic fungi are a major constraint to global agricultural productivity, leading to significant yield losses and increased dependence on chemical fungicides. Sustainable management of plant diseases has therefore gained considerable attention, with biological control emerging as an eco-friendly alternative. The present study was undertaken to evaluate the antagonistic activity of different Trichoderma spp. against selected soil-borne plant pathogenic fungi under in vitro conditions. Antagonistic potential was assessed using the dual culture technique on potato dextrose agar, and percent inhibition of mycelial growth was calculated. The results revealed significant variation among Trichoderma isolates in suppressing pathogen growth. Maximum mycelial growth inhibition ranging from 68.4% to 82.7% was recorded with Trichoderma harzianum, followed by Trichoderma viride (61.2%–74.5%), while comparatively lower inhibition (45.3%–56.8%) was observed with other isolates. The strong antagonistic activity exhibited by effective isolates was characterized by rapid overgrowth, hyphal coiling, and clear inhibition zones, indicating mechanisms such as competition, mycoparasitism, and antibiosis. Statistical analysis confirmed that the inhibition effects were significant (p ≤ 0.05). The study demonstrates that selected Trichoderma spp. possess substantial biocontrol potential against soil-borne pathogens and can be effectively utilized as sustainable alternatives to chemical fungicides. These findings highlight the role of Trichoderma-based biocontrol agents in environmentally safe plant disease management and support their further evaluation under field conditions.