广西香蕉细菌性软腐病病原鉴定及生物学特性研究  

Identification and biological characteristics of the pathogen causing banana bacterial soft rot disease in Guangxi

作　　者：杜婵娟[1] 杨迪[1] 付岗[1] 叶云峰[2] 潘连富[1] 张晋[1] DU Chanjuan;YANG Di;FU Gang;YE Yunfeng;PAN Lianfu;ZHANG Jin(Plant Protection Research Institute,Guangxi Key Laboratory for Biology of Crop Diseases and Insect Pests,Guangxi Academy of Agricultural Sciences,Nanning 530007,China;Institute of Horticulture,Guangxi Academy of Agricultural Sciences,Nanning 530007,China)

机构地区：[1]广西农业科学院植物保护研究所,广西作物病虫害生物学重点实验室,南宁530007 [2]广西农业科学院园艺研究所,南宁530007

出　　处：《植物保护》2019年第5期148-156,共9页Plant Protection

基　　金：国家自然科学基金(31560006);广西自然科学基金(2016GXNSFBA380173,2017GXNSFDA198002);广西农业科学院科技发展基金(桂农科2018JZ12,2018YM24,2018YT15)

摘　　要：为明确引起广西香蕉细菌性软腐病的病原,采用组织分离法从染病的香蕉组织中分离病原菌,通过柯赫氏法则验证其致病性。对病原菌进行形态学观察、分子鉴定、生理生化测试及生物学特性测定。结果表明,从染病蕉头和蕉果分离到的病原菌,其菌株的形态特征、生理生化测试结果与Dickeya sp.基本一致,16S rDNA基因序列与Dickeya属细菌的同源性达99%;其最适培养温度为28℃,最适pH为7.0。病原菌的dnaX、gryB和recA基因序列与D.zeae的同源性均在97%以上。多基因系统发育树显示,病原菌与所有的D.zeae细菌聚在同一个最小进化分支里,自展支持率为100%。根据以上结果,将引起广西香蕉细菌性软腐病的病原菌鉴定为Dickeya zeae。同时,测定7种杀菌剂对GR-1菌株的室内毒力,46%氢氧化铜WG的EC 50最低,为186.69 mg/L;其500倍稀释液对GR-1菌株的抑菌效果最好,达76.89%。In order to clarify the pathogen causing banana bacterial soft rot in Guangxi,the pathogenic bacteria were isolated by tissue separation method from tissues of diseased banana,and their pathogenicity were verified through Koch’s Rule.The pathogen was identified based on morphology,physiological and biochemical characteristics,molecular identification and biological characteristics.The results showed that the pathogenic bacteria were isolated from the pseudostem and fruit of diseased bananas.Their morphological characteristics,physiological and biochemical results were basically consistent with Dickeya sp.,and the 16S rDNA gene sequences shared 99%similarity with that of Dickeya sp..The optimum temperature for the pathogenic bacterium was 28℃,and the optimum pH was 7.0.The homology of dnaX,gryB and recA gene sequences between the pathogenic bacterium and D.zeae was more than 97%.Multiple-gene phylogenetic analyses indicated that the pathogen and all the bacteria of D.zeae clustered in the same evolutionary branch,with a self-supporting rate of 100%.According to these results,the pathogen causing banana bacterial soft rot in Guangxi was identified as Dickeya zeae.Furthermore,the toxicity of 7 types of bactericides against strain GR-1 were tested.The EC 50 of copper hydroxide 46%WG was the lowest among the tested bactericides(186.69 mg/L),and its 500 times dilution had the best inhibition effect on GR-1 strain,up to 76.89%.

关 键 词：香蕉 Dickeya zeae 病原鉴定 多基因系统发育 生物学特性 

分 类 号：S436.681[农业科学—农业昆虫与害虫防治]