草莓病害生物防治初探

A Preliminary Study on Biocontrol of Strawberry Diseases

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 spp. were isolated from 20 rhizosphere soil samples by usingdilute plate technique. 22 strong antagonistic strains to Botrytis cinerea Person and/or Rhizoctonia solani Kuhn were screened w ith the differed antagonism procedure. Among which, 9 hadstrong antagonistic activity to one kind of pathogenic fungus and weak to another; 5 had strongantagonistic activity to both of the pathogenic fungi. Strain 10, 21, 34 and 63 had antagonisticactivity to Macrophoma kuw atsukai Hara and Helm inthosporium turcicum Pass. too, whichindicated that they had wide anti fungous spectrum. And strain 10 and 12 had strong antagonisticactivity to all of the pathegenie fungi tested. The antatagonistic subatances of 9 strains con id notpass through dialysis tubing, and could be precipititated by (N H4 )2SO4, and regarded as proteinspreliminarily. The antagonistic activity of crude proteins was tested with the plate diffusionmethod. The screened strong antagonistic bacteria had the potential to be used in biocontrol, andshould he regarded as valuable resources.