一串红穿孔病病原鉴定和初侵染源分析  

Identification of the causal agent of shot hole disease on Salvia splendens and primary infection source analysis

作　　者：彭勇政[1] 朱章飞 陈功友[1] 李秀丽 PENG Yongzheng;ZHU Zhangfei;CHEN Gongyou;LI Xiuli(School of Agriculture and Biology,Shanghai Jiao Tong University,Shanghai 200240,China;School of Biological and Food Engineering,Suzhou University,Suzhou Anhui 234000,China)

机构地区：[1]上海交通大学农业与生物学院,上海200240 [2]宿州学院生物与食品工程学院,安徽宿州234000

出　　处：《植物病理学报》2022年第4期522-528,共7页Acta Phytopathologica Sinica

基　　金：上海市科技兴农项目(2020-02-08-00-08-F01462);安徽省“六卓越,一拔尖”项目(2019zyrc106)。

摘　　要：2021年夏季,受台风“烟花”影响,上海市奉贤区海湾镇大面积一串红种苗突发穿孔病,本文按照柯赫氏法则鉴定病原物并进行初侵染源分析。从田间病样中分离出的黄色分离物YchA回接一串红形成穿孔症状,在非寄主本氏烟草上可激发过敏反应。16S rDNA序列分析显示YchA为黄单胞菌属;以持家基因fyuA、gyrB、rpoD进行多位点序列分析(Multi-locus sequence analysis, MLSA)发现,菌株YchA与核桃细菌性黑斑病菌(Xanthomonas arboricola pv.juglandis, Xaj)亲缘关系最近;Biolog鉴定系统分析显示,一串红穿孔病病原为Xaj的可能性约为68%。对育苗基质、种子和灌溉水的检测发现,种子和灌溉水带菌。这些结果表明,一串红细菌性穿孔病的病原为树生黄单胞菌(X.arboricola),可能是一个新致病变种;种子带菌是病害的初侵染来源,灌溉水带菌扩散。Affected by the typhoon "Fireworks" in summer of 2021, a shot hole disease on Salvia splendens was rapidly and widely occurred in Haiwan Town of Fengxian District in Shanghai. This work aimed to identify the causal agent of the disease according to Koch′s postulates and to study the primary infection sources. A yellow isolate YchA from field diseased samples was proved to cause the shot hole disease on S. splendens and induced hypersensitive response(HR) in non-host Nicotiana benthamiana. Multi-locus sequence analysis(MLSA) of 16 S rDNA and the house-keeping genes fyuA, gyrB and rpoD showed that the isolate YchA had the most close phylogenetic relationship to Xanthomonas arboricola pv. juglandis. The results of Biolog analysis revealed that the possibility of YchA belonging to X. a. pv. juglandis is about 68%. PCR-based detection of matrix formula, seed, and irrigation water showed that YchA surviving in seed and irrigation water. Taken together, the causal agent of bacterial shot hole on S. splendens is possibly a new pathovar of X. arboricola. The primary infection source of the shot hole disease is seed-borne pathogen and pathogen-contaminated irrigation which leads to the epidemic under typhoon conditions.

关 键 词：一串红 细菌性穿孔病 树生黄单胞菌 多位点序列分析 初侵染源 

分 类 号：S681.4[农业科学—观赏园艺]