Bio-efficacy of native antagonists against dry root rot of groundnut Caused by macrophomina phaseolina

Groundnut grown under rainfed and irrigated conditions is subject to various diseases among which, Macrophomina phaseolina causing dry root rot is an important pathogen causing considerable yield loss. Management of M. phaseolina using chemical fungicides has been the prevailing control method for over fifty years. But the pathogen was reported to have developed resistance to fungicides and the pathogen is very difficult to be destroyed by drenching the soil with fungicides. Hence, the present investigation was conducted to test the efficacy of native antagonists along with Glomus mosseae (AM fungi) individually and as combination for the management of M. phaseolina. Among the native antagonist, Trichoderma viride isolate (Tv7) and Pseudomonas fluorescens isolate (Pf5) effectively inhibited the mycelial growth and sclerotia of M. phaseolina and showed compatibility between them. The combination of T. viride (Tv7) and P. fluorescens (Pf5) recorded the maximum germination, shoot and root length of groundnut. In the field studies the treatment combination involving seed treatment + soil application with combination of T. viride (Tv3) and P. fluorescens (Pf7) plus soil application of G. mosseae recorded the minimum incidence of root rot, maximum biometrics of groundnut.