Biological control of phytopathogens using Trichoderma isolated from rhizospheric soils of Uttarakhand

In the present investigation, thirty isolates of Trichodermae isolated from rhizhosperic soil samples of different crop plants morphologically characterized as T. harzianum and T. virens, were evaluated in vitro for their antagonistic potential against Rhizoctonia solani, Sclerotium rolfsii and Fusarium oxysporum. All the isolates exhibited the antagonistic effect against these phytopathogens under dual culture and hyphal growth of phytopathogens, was inhibited at the zone of contact with the hyphae of the antagonist. Isolates PB 2, PB 19 and PB 15 were recorded most aggressive to inhibit hyphal growth of R. solani, S. rolfsii and F. oxysporum, respectively. Out of 30 isolates excluding T. virens, 14 showed mycoparasitic ability by coiling around the hyphae of R. solani.