Biocontrol of Rhizoctonia solani Kiihn Using Fermentative Solution of Streptomyces corchorusii Strain NF0919

A strain of Streptomyces corchorusii( NF0919) antagonistic to Rhizoctonia solani Kuhn was isolated,which produced alkyl glycoside with high antifungal activity. To investigate the antifungal activity of Streptomyces corchorusii strain NF0919,the treatments amended with the non-sterilized supernatant resulted in the highest growth inhibition rate of about 100% at a concentration of 20%. The antifungal compound,which inhibited the growth of Rhizoctonia solani Kuhn,was extracted by Et OAC and purified by silica gel,Sephadex LH-20 column,and HPLC,where an active fraction was confirmed by LC-MS and NMR techniques. These results suggested that NF0919 had a high potential in the biocontrol of Rhizoctonia solani Kuhn,which was mainly due to surface active agent APG.