An in vitro test was conducted to find out the
comparative antagonistic potential of 20 selected Trichoderma
isolates against R. solani isolate SR1 on PDA by dual
culture technique [19]. Discs of mycelium (5-mm diameter)
of each of the selected fungal isolates were cut from
the edge of an actively growing fungal colony with a cork
borer (5-mm diameter). One mycelial disc of individual
isolates of Trichoderma and one disc of a test fungal
pathogen were placed simultaneously on the edge of each
PDA Petri plate at opposite directions. Three replicate
plates were used for each isolate of Trichoderma and a test
pathogen. The plates were arranged on the laboratory
desks following a completely randomized design. The
plates receiving only discs of R. solani served as controls.
The plates were incubated in the laboratory at an ambient
temperature of 25 3 8C. Thereafter, inhibition percentages
of the R. solani were calculated based on the growth of the
pathogen on PDA plates following the formula suggested by
Sundar et al.