Screening and Identification of Actinomycetes from Special Habitats

50 actinomycete strains were isolated from 6 soil samples which collected from chemical companies surroundings in Guangxi and Jiangsu through soil dilution method.Using Verticillium dahliae Kleb,Fusarium oxysporum f.sp.vasinfectum and Fusarium oxysporum f.sp.niveum as target pathogens,5 antagonistic actionmycete strains were screened in vitro and in pot.The results showed that the strains JSGF4,JSGF10 and GXCK1 have obvious antagonistic effects on both mycelium growth and conidia germination of 3 target pathogens.In pot experiments,the preventing effects of 5 actinomycete strains on V.dahliae were significant,and among them,the preventing effect of the strain JSGF10 was as high as 90.0%.The 4 high activity strains were identified on the morphological,cultural,physiological and biochemical characteristics.The results showed that the strain JSGF4 was identified as Streptomyces rimosus,the strain JSGF10 and GXCK1 were Streptomyces albus,and the strain GXDM6 belonged to Streptomyces griseus.