香蕉枯萎病拮抗放线菌的分离鉴定及抑菌机理分析  

Isolation and Identification of Actinomycetes JRGG-11 and Its Antagonistic Mechanism Against Banana Fusarium Wilt

作　　者：张惠茜 王尉 周登博[2] 云天艳 陈宇丰[2] 谢江辉[2] ZHANG Huixi;WANG Wei;ZHOU Dengbo;YUN Tianyan;CHEN Yufeng;XIEJianghui(College of Horticulture,Hainan University,Haikou,570228;Institute of Tropical Bioscience and Biotechnology,Chinese Academy of Tropical Agricultural Sciences,Haikou,571101,China)

机构地区：[1]海南大学园艺学院,海口570228 [2]中国热带农业科学院热带生物技术研究所,海口571101

出　　处：《中国南方果树》2021年第3期1-8,共8页South China Fruits

基　　金：海南省自然基金创新研究团队项目(320CXTD441);国家香蕉产业技术体系项目(CARS-31)资助。

摘　　要：为丰富香蕉枯萎病生防菌资源,探究其抑菌机理,从润楠Machilus pingii根系土壤中分离筛选对香蕉枯萎病菌具有拮抗作用的放线菌,基于16S rRNA序列进化分析和生理生化特征,鉴定其种属。利用激光共聚焦显微镜评测盆栽试验的防控效果,并通过扫描电镜、透射电镜分析其对枯萎病菌孢子形态结构及超微结构的影响。结果表明,试验筛选出1株拮抗效果较好的放线菌,鉴定为链霉菌属,命名为JRGG-11。该菌对枯萎病菌4号生理小种(Foc 4)的抑菌率为(80.48±1.49)%,发酵液的抑菌率为(58.77±1.31)%,发酵液对Foc 4的盆栽防控效果为83.10%。菌株JRGG-11提取物对Foc 4菌丝生长抑制的EC50为18.70μg/mL,当用4×EC50处理时,Foc 4菌丝形态和细胞完整性被严重破坏,孢子萌发完全被抑制。说明链霉菌JRGG-11具有较好的生防潜能。To enrich the resources of banana fusarium wilt biocontrol bacteria and explore the antibacterial mechanism, actinomycetes with antagonistic effects on banana fusarium wilt were isolated and screened from the root zone soil of Machilus pingii. The candidate strain was identified by 16 S rRNA sequence analysis and physiological and biochemical characteristics. The inhibitory effect was comprehensively evaluated with pot experiments by using confocal laser scanning microscope. Effects of actinomycetes on the morphology and ultrastructure of spores of banana fusarium wilt pathogen were investigated by a scanning electron microscope and a transmission electron microscope. A strain marked as JRGG-11 showed a high antagonistic effect on Foc TR4. The inhibition rates of strain JRGG-11 and its extracts were 80.48±1.49% and 58.77±1.31%, respectively. Strain JRGG-11 was identified as Streptomyces sp..The pot experiment showed that the fermentation broth can obviously inhibit the infection of Foc 4. The inhibition rate was 83.1%. EC50 value of the extracts from JRGG-11 against Foc 4 was 18.70 μg/mL. The morphology and cell integrity of mycelia of Foc 4 were seriously destroyed and the conidia germination was completely inhibited under treatment with 4×EC50 of extract. The results showed that Streptomyces sp. JRGG-11 has a great potential on biological control of pathogen.

关 键 词：香蕉枯萎病 放线菌 鉴定 防控效果 抑菌机理 

分 类 号：S436.68[农业科学—农业昆虫与害虫防治]