Evaluation of fungal and bacterial antagonists from groundnut rhizosphere for biological control of Macrophomina phaseolina (Tassi) Goid. causing dry root rot of groundnut

In India root rot caused by Macrophomina phaseolina (Tassi.) Goid. causes considerable losses to groundnut. Although some chemical fungicides are known to be effective, such chemicals can be harmful for environment. Hence, disease containment through an eco-friendly biocontrol approach, using natural antagonistic microflora, is becoming an inevitable component in the integrated management strategy of plant diseases. Hence, the present study was conducted with an objective to isolate fungal and bacterial antagonists viz., Trichoderma sp., Pseudomonas sp. and Bacillus sp. from the rhizosphere of groundnut and to screen them for their plant growth promoting attributes and antagonistic properties against dry root rot causing pathogen M. phaseolina. The study has clearly brought out the efficacy of the native isolates of T. viride (Tv7), P. fluorescens (Pf5) and B. subtilis (Bs3) in reducing the mycelial growth and sclerotia of M. Phaseolina causing dry root rot of groundnut. Further, these antagonistic isolates showed plant growth promoting activity and could be successfully used for biological management of root rot of groundnut.