Bio-efficacy of Trichoderma species against Pigeonpea wilt pathogen

Three biocontrol agent viz., Trichoderma viride, Trichoderma virens and Trichoderma harzianum were evaluated to test the antagonism against Fusarium udum under in vitro conditions. All the three biocontrol agents have the potential of parasitizing the growth of Fusarium udum in vitro. The rate of parasitism was found fastest in T. viride (61.12% over growth in 96 hrs) than T. virens and T. harzianum. The volatile compounds from Trichoderma viride suppressed the mycelial growth of Fusarium udum by 43.13% and found effective when compared to Tricho-derma virens and Trichoderma harzianum. Non-volatile compounds or culture filtrate from Trichoderma virens at 15% concentration shows complete mycelial inhibition of the test fungi. The antagonist T. virens was chosen to be the most promising bio-control agent for F. udum.