Efficacy of antagonists against Macrophomina phaseolina inciting dry root rot disease of groundnut

Abstract

Groundnut (Arachis hypogaea L.) is an important oilseed crop in Indian continent. Groundnut is being infected by several fungal, bacterial and viral diseases but dry root rot caused by Macrophomina phaseolina (Tassi) Goid. is considered as the most devastating disease in all the groundnut growing areas of Rajasthan. Trichoderma viride, T. harzianum, T. atroviride, Pseudomonas fluorescens and Bacillus subtilis gave distinct antagonistic reactions, showing stunting of Macrophomina phaseolina colony and clear zone of inhibition between colonies of antagonist and the pathogen was developed. Maximum growth inhibition was recorded in Trichoderma viride followed by T. harzianum. Trichoderma viride and T. harzianum in combination as seed treatment and soil application were most effective in minimising the root rot incidence followed by T. viride in combination with Pseudomonas fluorescens