香蕉内生细菌G9R-3分离鉴定及其拮抗香蕉枯萎病菌活性评价

Isolation and Identification of Endophytic Bacteria G9R-3 in Banana and Antagonistic Activity Evaluation Against Fusarium oxysporum f.sp.cubense Race 4

【目的】分离、鉴定香蕉内生细菌G9R-3并评价其拮抗香蕉枯萎病菌(Fusarium oxysporum f.sp.cubense race 4,Foc4)活性,为开发利用该菌株防控香蕉枯萎病(Fusarium wilt)提供理论依据。【方法】通过形态学观察、生理生化特性分析及分子检测鉴定从桂蕉9号健康香蕉植株根部分离的一株香蕉内生细菌G9R-3菌株。分别运用平板对峙法、生长速率法、平板对扣法及杯苗灌根接种法,分析菌株G9R-3拮抗香蕉枯萎病菌的活性并综合评价其防效。【结果】菌株G9R-3鉴定为解淀粉芽孢杆菌(Bacillus amyloliquefaciens),对香蕉枯萎病菌平板菌落的抑制率为83.05%;发酵上清液对Foc4菌丝生长抑制率为42.35%;挥发性气体对Foc4菌丝生长抑制率为58.64%。对盆栽香蕉枯萎病的防控结果表明,菌株G9R-3对香蕉枯萎病菌具有拮抗活性,其中接种桂蕉1号的相对防效为65.00%,接种红研2号的相对防效为29.91%,接种万钟4号的相对防效为16.11%,接种桂蕉9号的相对防效为48.83%。【结论】G9R-3是一株对香蕉枯萎病菌具有拮抗活性的内生解淀粉芽孢杆菌,能提高盆栽抗、感病香蕉品种的防治效果。

【Objective】A banana endogenous bacteria G9 R-3 was isolated and identified from the roots of healthy banana plant No.9.The strain was evaluated for its activity against Fusarium oxysporum f.sp.cubense race 4(Foc4),which provided a theoretical basis for the development and utilization of the strain to prevent and control Fusarium wilt.【Method】A banana endogenous bacteria G9 R-3 was isolated and identified from the roots of healthy banana plant No.9 by morphological observation,physiological and biochemical analysis and molecular detection.The antagonistic activity and control efficacy against Foc4 were evaluated by plate sputum method,growth rate method,plate-to-button method and cup seedling root inoculation method.【Result】The strain G9 R-3 was identified as Bacillus amyloliquefaciens.The colony inhibition rate of strain G9 R-3 was 83.05%;The growth inhibition rate of Foc4 mycelium by fermentation supernatant was 42.35%;The inhibition rate of volatile gas to Foc4 mycelium was 58.64%.The evaluation results of potted plant control of Fusarium wilt showed that the strain G9 R-3 had antagonistic activity against Fusarium wilt.The relative control effect of strain G9 R-3 inoculated with Guijiao No.1 was 65.00%,and the relative control effect of inoculation Hongyan No.2 was 29.91%.The inoculation of Wanzhong No.4 was relative.The control effect was 16.11%,and the relative control effect of inoculation of Guijia 9 was 48.83%.【Conclution】G9 R-3 is an endophytic B.amyloliquefaciens which has antagonistic activity against F.oxysporum f.sp.cubense race 4,and its activity evaluation shows that it can improve the disease resistance of susceptible and resistant banana varieties.