Abstract:[Objective] Streptomyces ZM-16 has been proved to possess great anti-bacteria effect to many strains of bacteria. The main active component of the fermentation products is actinomycin D. This study aims at the investigation of the antifungal activities of the fermentation products of Streptomyces ZM-16 and the enhancement of the active substance yield of the strain by mutation breeding, in order to develop and improve its practical application in bio-control field of plant diseases. [Methods] Obtain the active fermentation products with liquid fermentation of the strain and conduct a cruel extraction; test the antimicrobial effect of the cruel extracts on 11 kinds of plant pathogenic fungi by inhibition zone method; improve the strain by microwave mutation breeding and antibiotics resistance screening. [Results] The cruel extracts solution showed antimicrobial effect on all the 11 kinds of plant pathogenic fungi. Among them, it possessed greatest inhibitive effect on Glomerella cingulated, Sclerotinia sclerotiorum and Fusarium graminearum. After induced mutation by microwave, a rifampin resistant mutant strain was screened out, whose yield of actinomycin D was enhanced 36.75%. The study on genetic stability of passage showed that the mutant strain was stable after 10 generations. [Conclusion] The fermentation products of Streptomyces ZM-16 have great inhibitive effect on most plant pathogen fungi; moreover, the yield of active products was enhanced after genetic improvement. These results demonstrated that the strain has a high value of practical application.
