Efficiency of Locally Isolated Trichoderma virens for Controlling Rice Brown Leaf Spot Disease Caused by Bipolaris oryzae

Abstract

Rice brown leaf spot disease caused by Bipolaris oryzae is one of the major rice diseases in Sri Lanka and which effects the rising concerns of food safety. Biological control of brown spot disease is an alternative method for synthetic fungicide. Trichoderma is a widely studied bio-control agent and it is proven to be effective against a wide range of plant pathogens. In the present study a locally isolated Trichoderma virens was tested against the brown spot pathogen, Bipolaris oryzae in in-vitro conditions. Identity confirmation was done by using morphological methods and molecular through Polymerase Chain Reaction (PCR) with ITS 1 and ITS 4 primers and subsequent homology search. Antagonism of T. virens against B. oryzae was tested using dual culture technique. Locally isolated Trichoderma virens had an inhibition ability of 75 % in dual culture test. Finally, it is evident that Trichoderma virens can successfully inhibit growth of the pathogen under in vitro conditions.