Potential antagonistic phylloplane fungi from Stevia rebaudiana Bert. as bio-control of aerial blight disease caused by Rhizoctonia solani

摘要

Stevia rebaudiana Bert. is, a natural low calorie sweetener, subjected to isolate potential fungal antagonist. Phylloplane fungi were used as biocontrol of aerial blight disease caused by Rhizoctonia solani. A survey of fungal pathogens of S . rebaudiana was conducted in three different regions of Uttarakhand state. R. solani was the causative agent of aerial blight on Stevia leaves and found pathogenic to the weed. The morphological study and antagonistic tests were executed in this study. Twenty-two fungal species were isolated and tested as antagonist against R. solani. Trichoderma hamatum , Aspergillus sp., Curvularia lunata and Emericella nidulans antagonised R. solani by overgrowing on it. Metabolites produced by thirteen fungal species affected the pathogen by antibiosis. This finding showed that T . hamatum and Aspergillus sp. exhibited the highest antagonist effects on R. solani and could be helpful in the management of aerial blight disease of Stevia.