关键词: 玉竹, 锐顶镰孢菌, 拮抗, 解淀粉酶芽孢杆菌, 生物防治

Abstract: Using the plate confrontation assay, 16 strains with antagonistic effects on Fusarium acuminatum were screened from 90 bacteria isolated from the rhizosphere of Polygonatum odoratum growing in medicinal garden of Jilin Agriculture Science and Technology University. The growth speed rate method was used for measuring the antimicrobial spectrum of G-27 owing the optimal bacteriostasis in vitro, and pot trails were carried out to assess its control effect to Cercospora chinensis in vivo. The results indicated that the inhibition rate of strain G-27 fermentation broth to F. acuminatum was 87.67%. Additionally, it had promising antimicrobial effect to over 10 kinds of plant pathogens, for example, Phytophora capsici, indicating it had broad-spectrum antimicrobial effects. The strain G-27 had significant control efficacy(P<0.05)compared with the pesticides treatments, and the protective and the therapeutic efficacy of the aseptic filtrate of G-27 reached 70.01% and 71.52% with no dilution, even control efficacy of the 20 times dilution of fermentation broth exceeded 50% in pot trails. According to morphologic, physiological and biochemical characteristics and 16S rDNA sequence analysis, strain G-27 was identified as Bacillus amyloliquefaciens.

Key words: Polygonatum odoratum, Fusarium acuminatum, antagonistics, Bacillus amyloliquefaciens, bio-control