In vitro antagonistic activity of bioagents against Sclerotium rolfsii causing stem rot of Aster (Callistephus chinensis L.)

Aster (Callistephus chinensis), a widely cultivated ornamental plant. The area, production and productivity of China aster have practically stagnated in recent decades. Among the various reasons the plants suffering from different diseases is one of the major reasons. Among the different diseases stem rot caused by S. rolfsii leads to extensive financial loss to growers. The pathogen was isolated from infected stems exhibiting the classic symptoms of stem rot disease. The Potato Dextrose Agar (PDA) medium was used to grow the fungal colony. A variety of morphological characteristics, including mycelium, colony, and sclerotia formation, were used to identify the pathogen. Conventional management using chemical fungicides poses significant environmental and health concerns, emphasizing the need for sustainable alternatives. This study explores eco-friendly disease management strategies through the use of antagonistic microorganisms against S. rolfsii. The integration of such biocontrol agents showing a promising and environmentally approach for managing stem rot in aster, reducing reliance on chemical fungicides, and promoting sustainable floriculture practices. The results indicated that Trichoderma asperellum (5.4cm) which was significantly superior over all other bioagents inhibited the growth of S. rolfsii, reducing mycelial expansion and sclerotia formation. Future research should focus on field trials to validate these in-vitro findings and explore the potential synergistic effects of combining different bioagents. This study contributes to the development of integrated disease management strategies for stem rot in aster plants, promoting healthier and more resilient crops.