植物病原真菌的拮抗放线菌筛选

[目的]筛选对植物病原真菌有抑制作用的拮抗放线菌。[方法]以棉花枯萎病菌为靶标菌,采用稀释平板法从4份土样中分离放线菌,筛选拮抗放线菌并测定其理化特性和抗菌谱。[结果]分离到113株放线菌,获得拮抗菌株23株,其中6株对棉花枯萎病菌抗性较强。除332#菌株外,其他菌株均可液化明胶。除323#菌株外,其他菌株均可胨化牛奶。6株拮抗放线菌的利用淀粉能力都较强。219#和323#可分解纤维素。121#3、23#3、27#和430#最适生长温度约为28℃,219#和332#分别为28~35℃和35~40℃。6菌株最适生长pH值均为6~7。6菌株对棉花枯萎病菌有较强的抑制作用。菌株121#、219#抗菌谱较广,对真菌抗性明显。[结论]121#3、27#和430#在初步液体培养中生长良好,产生较高抗菌活性物质,可用于抗真菌代谢产物的研究和应用。

Screening Antagonistic Actinomycetes against Plant Pathogenic Fungi

The objective of the research was to screen antagonistic actinomycetes that had inhibition effects on plant pathogenic fungi.With cotton-wilt fusarium as target fungus,actinomycetes were separated from 4 soil samples by diluting flat method to screen antagonistic actinomycetes and determine their physical and chemical characteristics and antifungal spectrum.113 strains of actinomycetes were separated and 23 strains were antagonistic actinomycetes,in which 6 strains had strong resistance to cotton wilt fusarium.Except 332# strain,other strains could all liquefy glutin.Except 323# strain,other strains could all peptonize milk.6 strains of antagonistic actinomycetes all had strong capabilities of utilizing starch.Strains of 219# and 323# could decompound cellulose.The optimum growth temperature for strains of 121#,323#,327# and 430# was about 28 ℃,that of 219# and 332# strain were 28～35 ℃ and 35～40 ℃ respectively.The optimum pH value for growth of 6 strains were all 6～7.6 strains had strong inhibitory effect on cotton wilt fusarium.Strains of 121# and 219# had broad antifungal spectrum and obvious resistance to fungi.strains of 121#,327# and 430# grew well in preliminary liquid culture and produced higher antimicrobial active substances,which could be used in the research and application of antifungal metabolites.