Antagonistic Potential of Some Isolated Soil Fungi Against Brown Root Rot Disease of Tea in Barak Valley of Assam

Abstract

As tea is a long duration perennial crop it is very much prone to attack by several pathogens. Brown root rot disease (Fomeslamoensis (Murr.) Sacc. and Trott) is the one of the important primary root disease of teawhich, inhibits plant growth, causes yellowing and wilting of leaves, defoliation, branch dieback, and affect plant death.An antagonist is broadly defined as an opponent or adversary. In biological control of plant pathogen, antagonists are biological control agents (BCA) with the potential to interfere in the life process of plant pathogens. In the present work more than 20 fungal isolates were tried and out of which four isolate have exhibited antagonistic activity against the pathogen F. lamoensis.These four selectedisolates were found to be fast growing and on coming close to the pathogen then into it, eventually overgrew, except Penicillium sp. No clear inhibition zone was noticed in between isolates and F. lamoensis. The genus Trichoderma showed ‘F’ type of colony interaction. Among of these Trichodermaviride and T. citrinoviride showed highest antagonism followed by Aspergillusniger and Penicillium spp.