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用平板稀释法从２０份根围土样中分离出６７株芽孢杆菌。用异步培养法筛选出对草莓灰霉菌和立枯丝菌核有强拮抗作用的菌株２２个，其中对２种病原菌有一强一弱拮抗作用的菌株９个，对２种病原菌均有强拮抗作用的菌株５个。菌株１０，１２，３４和６３还对梨轮纹病菌和玉米大斑病有拮抗作用，表现为广谱抗菌丝，其中菌株１０和１２对４种病原真菌均有强拮抗作用。９株拮抗菌的抗菌物质不能透过透析袋，可被硫酸铵沉淀，初步确定为蛋白质，并且用平极扩散法检测了蛋白粗提液的抗菌活性。筛选出的拮抗菌均有用于生物防治的潜力，应被视为宝贵资源。
67 strains of Bacillus were isolated from 20 rhizome samples by plate dilution method. Twenty-two isolates were screened by asynchronous culture to strongly antagonize strawberry gray mold and rhizoctonia solani, of which 9 had strong and weak antagonistic activity against 2 pathogenic bacteria and had strong antagonism against 2 pathogens Of the five strains. Strains 10, 12, 34 and 63 also antagonized the pathogen Peiropuranthylospora and Zea mays. They showed broad-spectrum antimicrobial silkworms, of which strains 10 and 12 had strong antagonism against the four pathogenic fungi. Antibacterial substances of 9 strains of antagonistic bacteria could not permeate the dialysis bag and could be precipitated by ammonium sulfate, initially identified as protein, and the antimicrobial activity of protein crude extract was detected by flat-plate diffusion method. The antagonistic bacteria that are screened have the potential for biological control and should be considered as valuable resources.