Synergistic antifungal activity of the culture filtrates of Serratia marcescens strain B2 and chemical fungicides against the sclerotial viability of the rice sheath blight pathogen, Rhizoctonia solani

Abstract

Serratia marcescens strain B2 is an antagonistic bacterium that inhibits the fungal growth of Rhizoctonia solani Kühn AG-1 IA and suppresses the rice sheath blight caused by R. solani AG-1 IA. The sclerotial germination of R. solani AG-1 IA decreased when the sclerotia were incubated in the culture filtrate of the strain B2. The antifungal activity of the culture filtrate was enhanced by the treatment in combination with low concentrations of the chemical fungicides, flutolanil, pencycuron and validamycin. There was a synergistic antifungal activity produced by the culture filtrate of the strain B2 and chemical fungicides on the sclerotial viability of R. solani AG-1 IA.