Development of Bioformulations for the Management of Blackgram Dry Root Rot Caused by Rhizoctonia bataticola (Taub Butler)

An attempt was made to control dry root rot using consortia of bioinoculants. A total of 10 fungal (Trichoderma) and 30 bacterial (Pseudomonas and Bacillus) isolates were collected and screened for their antagonistic activity against mycelial growth of Rhizoctonia bataticola under in vitro condition. Among these, Trichoderma (TL1), Pseudomonas fluorescens (PfUL(A)) and Bacillus subtilis (BsOP2) isolates exhibited maximum inhibition. As results of the compatibility of the biocontrol agents revealed that P. fluorescens strains were compatible with B. subtilis and Trichoderma but B. subtilis strains were not compatible with Trichoderma strains. The biocontrol consortia consisting of P. fluorescens (PfUL(A)) and B. subtilis (BsOP2) + Farm Yard Manure (FYM) + Neem cake was found to be promising in reducing dry root rot incidence under field conditions. The biocontrol consortia also induced high level of defense - related enzymes videlicet phenylalanine ammonia lyase, catalase, peroxidase and polyphenol oxidase activity.