In-Vitro and In-Vivo Efficacy of Agrochemicals, Biological Derived Formulations and Bioagents Against Sheath Blight of Rice

Rhizoctonia solani Kuhn (Teleomorph: Thanatephorus cucumeris (Frank) Donk) is a soil-borne, necrotrophic fungus belonging to the division Basidiomycota Sheath blight is one of the most important and widespread diseases affecting rice in all major rice-growing regions of the world and causes significant reductions in grain yield. In India, rice sheath blight has been reported to cause yield losses of up to 54.3%. Sheath blight management was evaluated through in vitro and in vivo studies using agrochemicals, biologically derived formulations and bioagents. Under in vitro conditions, Propiconazole 25% EC (T₄) exhibited the highest mycelial growth inhibition (92.95-96.82%), whereas Pyrazosulfuron ethyl 10% WP (T₂) was the least effective. Among biologically derived formulations, Beejamrit (T₂) showed the highest efficacy, while Agniastra recorded the lowest growth inhibition. In bioagent evaluation, Trichoderma viride (T₁) showed maximum growth inhibition (36.61%), whereas PSF 173 was least effective. Under in vivo conditions, Propiconazole 25% EC (T₄) resulted in the minimum disease incidence (12.11%), while Pyrazosulfuron ethyl 10% WP showed the highest incidence. Among biologically derived formulations, Beejamrit (T₂) recorded the lowest disease incidence (16.62%), whereas Agniastra (T₄) showed the highest (26.24%). In bioagent treatments, Trichoderma viride (T₂) effectively reduced disease incidence (18.68%), while PSF 173 (T₃) recorded the maximum incidence (22.98%). These results highlight the comparative efficacy of chemical and biological approaches for managing sheath blight disease of rice.