芒果炭疽病拮抗菌L18-7菌株的筛选、鉴定及拮抗机制研究  

Screening,identification and antagonistic mechanism of antagonistic bacteria strain L18-7 against mango anthracnose

作　　者：蒋攀婷 伍玉玲 何昊哲 蒙姣荣[1] 罗慧[2] 方中斌[2] 李界秋[2] JIANG Pan-ting;WU Yu-ling;HE Hao-zhe;MENG Jiao-rong;LUO Hui;FANG Zhong-bin;LI Jie-qiu(College of Agriculture,Guangxi University,Nanning 530004,China;Agri-animal Industrial Development Institute,Guangxi University,Nanning 530004,China)

机构地区：[1]广西大学农学院,南宁530004 [2]广西大学农牧产业发展研究院,南宁530004

出　　处：《西南农业学报》2023年第4期742-749,共8页Southwest China Journal of Agricultural Sciences

基　　金：广西重点研发计划项目(桂科AB21220001);国家现代农业产业技术体系广西芒果创新团队桂南综合试验站项目(nycytxgxcxtd-06-04);广西大学大学生创新创业训练计划项目(202010593297)。

摘　　要：【目的】筛选芒果炭疽病拮抗菌菌株,为芒果炭疽病的生物防治打下理论基础并提供菌种资源。【方法】以芒果炭疽病菌优势种亚洲炭疽菌(Colletotrichum asianum)为靶标,利用前期研究获得的37株芽胞杆菌(Bacillus spp.)进行对峙培养和离体接种防效试验,选择防效好的拮抗菌株种类,分析其拮抗机制。【结果】对峙试验结果显示,有10株拮抗菌对芒果亚洲炭疽菌的抑制率大于78.00%,其中菌株M12-5、L18-7、L19-3、 L17-3和M11-6的抑制率分别达96.24%、94.94%、94.10%、91.25%和90.00%。离体接种筛选获得对芒果亚洲炭疽菌具有明显防效的芽胞杆菌8株,其中菌株L18-7和L16-4的防效较佳,离体接种平均防效分别达83.00%和79.16%,二者间差异不显著(P>0.05)。结合形态特征、16S rDNA序列比对结果和基于rpoB基因序列构建的系统发育进化树分析结果,将菌株L18-7鉴定为贝莱斯芽胞杆菌(B.velezensis)。菌株L18-7能产生胞外蛋白酶和纤维素酶,在LB(Luria-bertani)培养基、牛肉膏蛋白胨(NA)培养基和马铃薯葡萄糖琼脂(PDA)培养基等5种培养基中均可产生活性拮抗物,携带mycB、ituA、yndJ、fenB和bacA等产抗生素相关基因。【结论】芒果炭疽病拮抗菌菌株L18-7鉴定为贝莱斯芽胞杆菌,该菌株在28℃下LB培养基上生长良好,能产生拮抗活性物质、胞外蛋白酶和纤维素酶,携带mycB、ituA、yndJ、fenB和bacA等产抗生素相关基因,可作为生防菌的种质资源加以利用。【Objective】The present paper aimed to screen antagonistic bacterial strains of mango anthracnose,so as to lay a theoretical basis for biological control of mango anthracnose and provide strain resources.【Method】Colletotrichum asianum,the dominant species of mango anthrax,was used as the target,and 37 strains of Bacillus spp.obtained in previous studies were used for confrontation culture and in vitro inoculation test.The antagonistic strains with obvious control effect were selected and their antagonistic mechanism was analyzed.【Result】The results of confrontation test showed that the inhibitory rates of 10 antagonists against C.asianum were more than 78.00%,among which the inhibitory rates of M12-5,L18-7,L19-3,L17-3 and M11-6 reached 96.24%,94.94%,94.10%,91.25% and 90.00%,respectively.Eight strains of Bacillus spp.with obvious control effect were obtained by in vitro inoculation,among which strains L18-7 and L16-4 had the best control effect,with the average control efficiency of 83.00%and 79.16%,respectively.There was no significant difference between them(P0.05).Combined with morphological characteristics,16S rDNA sequence and phylogenetic tree analysis based on rpoB gene sequence,strain L18-7 could be identified as B.velezensis.Strain L18-7 could produce extracellular protease and cellulase,and could produce active antagonists in five media including Luria-bertani(LB),beef peptone(NA)and potato glucose agar(PDA)etc.Strain L18-7 carried genes related to antibiotic production such as mycB,ituA,yndJ,fenB and bacA.【Conclusion】The antagonistic bacterium strain L18-7 of mango anthracnose was identified as B.velezensis.The strain grew well on LB medium at 28℃.It could produce antagonistic substances,extracellular protease and cellulase and carried related genes of antibiotics such as mycB,ituA,yndJ,fenB and bacA.It can be used as germplasm resources for biocontrol bacteria.

关 键 词：芒果 亚洲炭疽菌 贝莱斯芽胞杆菌 生物防治 抗生素产生相关基因 

分 类 号：S432.1[农业科学—植物病理学]