Trichoderma brevicrassum strain TC967 with capacities of diminishing cucumber disease caused by Rhizoctonia solani and promoting plant growth

摘要

Some Trichoderma species have been used as biocontrol agents in agriculture. In order to explore additional useful natural resources, a large scale survey of Trichoderma strains from China was conducted and T. brevicrassum strain TC967 was singled out. In vitro assays indicated that it showed high chitinase activity in agar medium, inhibited growth of the plant-pathogenic fungus Rhizoctonia solani (72.14%) in dual culture, and revealed strong mycoparasitic ability through coiling and penetrating hyphae of the pathogen. In vivo assays indicated that it was able to suppress the cucumber disease caused by R. solani to a low disease index (37.5%). Hyphae of strain TC967 colonized cucumber root surface, induced the expression of pathogenesis-related protein genes PR1, PR4 and PR5. In addition, strain TC967 promoted cucumber growth. This is the first report of T. brevicrassum having biocontrol potential and promoting cucumber growth.