Evaluation of microbial consortia against Sclerotium rolfsii Sacc. causing foot rot of wheat

Abstract

The microbial consortium (combination of bioagents) is being currently used for crop protection over single bioinoculant in order to overcome the inconsistent performance shown by the introduced biocontrol agent. Foot rot of wheatcaused by Sclerotium rolfsii Sacc. is a serious soil borne disease in rainfed areas of Karnataka. The biocontrol agents(Trichoderma harzianum IOF strain, (MH027645.1), Pseudomonas fluorescens IOF strain, (NAIMCC-B-01981),Bacillus subtilis IOF strain, (MT383652.1) and Neofusicoccum parvum (Endophyte) were evaluated against S. rolfsiiunder in vitro condition. The potentiality of bioagents against S. rolfsii was higher in the consortium compared to the singlebioagent. All four combination of bioagents (T. harzianum + P. fluorescens + B. subtilis + N. parvum) had shown superiorityover other treatments in arresting the mycelial growth of S. rolfsii (80.37%). Among three combination of bioagents, highestinhibition was recorded in T. harzianum + B. subtilis + N. parvum (78.52%) and the least inhibition was recorded in theT. harzianum + P. fluorescens + B. subtilis (74.57%). Among two combinations of bioagents, B. subtilis + N. parvum hasrecorded highest inhibition (72.96%) and least inhibition was observed in P. fluorescens + B. subtilis(45.56%). Amongindividual antagonists, N. parvum has proved maximum inhibition against S. rolfsii (47.41%) followed by T. harzianum(46.66%) and were statistically on par with each other. Least inhibition was recorded in P. fluorescens (14.07%) andB. subtilis (17.04%). However, the standard chemical check [(carboxin 37.5% + thiram 37.5%)WP] has shown cent per centof inhibition of pathogen.