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为获得对烟草黑胫病有较强生防效果的拮抗细菌,从健康烟草根际采集30份土壤样品,分离纯化得到347株细菌,经病原真菌定向筛选后得到1株对烟草黑胫病菌等病原真菌拮抗活性较好的细菌FB-16,其对烟草黑胫病菌的抑菌带宽为23mm。采用菌丝生长速率法、作用机制试验、温室防病试验测定FB-16的抑菌作用,并通过形态学特征、生理生化特征及16S rDNA序列分析对菌株进行鉴定。结果显示,菌株FB-16发酵液对烟草黑胫病菌菌丝生长抑制率为95.96%;其代谢产物对烟草黑胫病菌菌丝有致畸作用;菌株FB-16为解淀粉芽胞杆菌Bacillus amyloliauefaciens(Gen-Bank登录号为JN245982);饱和度25%硫酸铵获得的抑菌物质对烟草黑胫病菌的抑菌活性较高,抑菌圈直径达42.00 mm;FB-16活性产物处理的烟草植株在接种烟草黑胫病菌7天后的防治效果为69.96%。表明菌株FB-16在烟草黑胫病生物防治中具有潜在的利用价值。
In order to obtain antagonistic bacteria with strong biocontrol effect on tobacco black shank, 30 soil samples were collected from healthy tobacco rhizosphere and 347 bacteria were isolated and purified. One pathogen against tobacco black shank Fungus antagonistic activity of better bacteria FB-16, its inhibition of tobacco black shank pathogenic bacteria bandwidth of 23mm. The bacteriostasis of FB-16 was determined by mycelial growth rate, mechanism of action test and greenhouse preventive test. The strains were identified by morphological, physiological and biochemical characteristics and 16S rDNA sequence analysis. The results showed that the mycelial growth inhibition rate of strain FB-16 was 95.96%, and its metabolites had teratogenic effects on mycelium of Phytophthora nicotianae. FB-16 strain was Bacillus amyloliquefaciens -Bank accession number JN245982); antibacterial substances obtained by 25% ammonium sulfate saturation had higher antibacterial activity against tobacco blackleg, and the diameter of antibacterial circle reached 42.00 mm; while the tobacco plants treated with FB-16 active substance had a higher antibacterial activity after inoculation After 7 days, the control effect of tobacco black shank was 69.96%. It indicated that strain FB-16 had potential value in the biological control of tobacco black shank.