A Paradigm Shift towards Eco-Friendly Agriculture: Harnessing the Biocontrol Potential of Trichoderma spp. against Plant Pathogens

Soil-borne pathogenic fungi cause significant losses in crop production and represent a major challenge to sustainable agriculture. The excessive use of chemical pesticides to control these pathogens poses serious environmental and health risks to humans and other living organisms. Therefore, the development of eco-friendly and sustainable disease management strategies is essential. The present study aimed to isolate and identify soil fungi and to evaluate their potential as biological control agents against common soil-borne fungal pathogens. Soil samples were collected, and fungal isolates were obtained using standard mycological techniques, followed by identification based on morphological characteristics. Four species of Trichoderma such as T. harzianum , T. aureoviride , T. koningii , and T. pseudokoningi were screened for their antagonistic activity against selected pathogenic fungi using the dual culture technique under in vitro conditions. The results revealed that Trichoderma koningii was found to be more efficient than the other three Trichoderma species in inhibiting the radial growth of the tested fungal pathogens. T. koningii (73.33%) showed the highest inhibition against Mucor mucedo , followed by T. pseudokoningii (69.91%), T. aureoviride (68.75%), and T. harzianum (65.45%). In contrast, T. harzianum (16.66%), T. aureoviride (25.00%), T. koningii (28.33%), and T. pseudokoningii (30.83%) were found to be least effective against Aspergillus niger . The colonization percentage was highest in the case of T. pseudokoningii against Alternaria alternata (70.66%), followed by T. harzianum against Aspergillus terreus (69.33%) and T. koningii against Cladosporium cladosporioides (66.00%). The lowest colonization percentage was observed for T. harzianum against A. niger (23.33%). During the study, the biocontrol index was found to be highest for T. harzianum against C. cladosporioides (79.24%), followed by T. aureoviride against P. notatum (74.61%), T. pseudokoningi i against P. notatum (72.32%), and T. koningiiF. oxysporum (71.13%)respectively. The highest biocontrol index was recorded for T. harzianum against C. cladosporioides (79.24%), whereas the lowest was observed for T. pseudokoningii against A. terreus (43.36%). The tested pathogens also exhibited varying degrees of resistance to the Trichoderma species. Aspergillus niger showed the highest pathogenic resistance to T. koningii , followed by T. pseudokoningii and T. aureoviride , and the least resistance to T. harzianum . Similarly, A. flavus exhibited higher resistance to T. koningii , followed by T. pseudokoningii , T. harzianum , and T. aureoviride . These findings highlight T. koningii as a promising biocontrol candidate with strong antifungal activity. The study provides experimental evidence supporting the use of Trichoderma species as sustainable and eco-friendly alternatives to chemical fungicides, contributing to integrated disease management and environmentally safe agricultural practices.