In vitro evaluation of native bio agents isolates against stem rot of pigeonpea caused by Sclerotium rolfsii

Abstract

Sclerotium rolfsii is a well known soil borne polyphagous fungal pathogen present throughout the world causing diseases like stem rot and collar rot to a wide range of plants. In this present investigation, Sclerotium rolfsii which is known to cause stem rot disease was isolated from the infected pigeon pea plants collected from the experimental trails of AICRP on pigeon pea, Medziphema campus. Five native isolates of bioagents viz. Trichodermma harzianum, T. viride, T. koningii, Bacillus subtilis and Pseudomonas fluorescens which were isolated from the rhizosphere of pigeon pea crop using serial dilution technique. The bioagents were screened in vitro using dual culture plate technique to find the potential antagonists against Sclerotium rolfsii. Out of the three Trichoderma species, and two bacterial antagonists, Trichoderma harzianum was recorded with the highest inhibition of 52.70% against Sclerotium rolfsii, followed by T. viride with 43.00%, Bacillus subtilis (39.20%) and Pseudomonas fluorescens (38%), while the lowest inhibition was recorded from T. koningii with 37.70%.