| Eight strains, that is, J-l,J-6, J-7, J-8, J-ll, J-13, J-15 and J-19 obtained from the soils in the mango orchard of Nanning Cable Television Station, Guangxi and J-A strain provided by Microbiological Laboratory of Guangxi Academy of Agricultural Sciences were experimented on isolated leaves and field trials , and placed under pairing culture with anthracnose pathogen. It was found that J-15 strain and J-A strain had more powerful antagonism against anthracnose pathogen. The activities of polyphenol oxidase, phenylalanine ammonialyase and peroxidase in leaves and fruits of mango treated by specific concentrations of J-A strain and J-15 strain were higher than those of the control. It was supposed that pathogen-suppresssive substances produced by the antagonistic microorganisms and the raise of enzyme activity resulted in reduction of the disease severity after spraying them on the leaves and fruits of mango.Studies on biological characteristics showed that J-15 strain could grow and develop from 14?C to 45?C, but the optimum growth temperature was about 38 ?C. It could grow and develop between pH5. 0-9. 0, but the optimum pH was about 6.5. The highest utilization efficiencies for saccharide sources, nitrogen sources and amonia acid were glucose, beef extract and asparagines, separately. J-15 strain could grow well under the condition of 2.00%NaCl osmotic pressure.J-A strain could grow and develop from 10℃ to 32CC, but the optimumgrowth temperature was about 28?C. It could grow and develop between pH6.0~9.0, but the optimum pH was between 7.0~8.0. The highest utilization efficiencies for saccharide sources and nitrogen sources were disaccharide and niter, separately. And the growth of J-A strain required darkness. The spores of J-A could germinate from 10 癈 to 38癈, but the optimum temperature was about 36?C. They could germinate between pH6.0~9.0, but the optimum pH was between 7.0-9.0. The germination rate was the highest when the humidity was over 90%.
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