Potential of fungal and bacterial biocontrol agent under in vitro conditions against Macrophomina phaseolina causing pigeonpea stem canker

Abstract

Stem canker caused by Macrophomina phaseolina (Tassi) Goid is one of the most important and widespread and destructive diseases of Pigeonpea [Cajanus cajan (L.) Mill spaugh], causing responsible quantitative and qualitative losses. Present study was undertaken on the stem canker caused by M. phaseolina (Tassi) Goid of pigeonpea during 2023-24. A total of nine bioagents/antagonist i.e. Sevan fungal antagonists viz., Trichoderma asperallum, T. harzianum, T. lignorum, T. virens, Metarhizium anisopliae, Aspergillus niger and two Bacterial antagonists Bacillus subtilis and Pseudomonas fluorescens was evaluated in vitro against M. phaseolina, applying Dual culture technique. The bio efficacy of fungal and bacterial biocontrol antagonist on Macrophomina phaseolina (Tassi) Goid., which incite stem canker of pigeonpea were studied. In dual culture technique all the antagonist/bioagents evaluated, exhibited fungistatic/antifungal activity against test pathogen and significantly inhibited its growth over untreated control. Trichoderma harzianum was found most effective with significantly highest inhibition (97.29%) of test pathogen. The second and third inhibitor antagonists found were Aspergilus flavus (93.99%) and A. niger (92.92%). The bacterial antagonist were Bacillus subtilis (87.40%), Pseudomonas fluorescens (85.08%). These were followed by T. asperellum (84.09%), T. lingorum (78.26%), Metarhizhium anisopliae (59.87%) and T. koningii (34.57%), respectively of the test pathogens inhibition.