Antagonistic Potentiality of Trichoderma harzianum Against Cladosporium spherospermum, Aspergillus niger and Fusarium oxysporum

Abstract

Many species of genus Trichoderma are used as an important source of biological agents. The potential efficacy of Trichoderma harzianum against the pathogenic fungi like Cladosporium spherospermum, Aspergillus niger and Fusarium oxysporum was evaluated on the fungal growth by culture pattern in which radial growth extension rates of two categories of fungal colonies were analyzed. All the fungal species were isolated from the rhizosphere of Juglans regia L. and cultured on the separate sterilized potato dextrose agar (Hi Media). Antagonism of T. harzianum was observed when all the fungal isolates were grown on the same PDA petri-plate in vitro by using the dual culture techniques. Trichoderma harzianum had a discernible inhibitory effect on the growth of pathogens in dual culture. The mycelial growth of pathogenic isolates was noticeably constrained after a period of 10 days at the temperature of 25⁰C and pH of 5.6. T. harzianum caused the maximum growth inhibition in A. niger (75%) followed by C. spherospermum (72.2%) and F. oxysporum (25%) at the specific temperature and pH, which justifies that T. harzianum is a promising biological agent for restricting the wilt and other fungal diseases.

Keywords; Trichoderma harzianum, pathogenic fungi, antagonism, radial growth