一种引起成年桑树根部腐烂的病害及致病菌分离与初步鉴定  

Isolation and Primary Identification of the Pathogen Causing Root Rot Disease of Adult Mulberry Trees

作　　者：方水琴[1] 吴福安[1,2] 陈明胜[1,2] 陶恒平[1] 梁垚[1] 姜星[1] 程嘉翎[1,2] 韩红发 张洁花 

机构地区：[1]江苏科技大学生物与环境工程学院,江苏镇江212018 [2]中国农业科学院蚕业研究所,江苏镇江212018 [3]山西省蚕业科学研究院,山西运城044000

出　　处：《蚕业科学》2011年第5期785-791,共7页ACTA SERICOLOGICA SINICA

基　　金：现代农业产业技术体系专项(No.CARS-22)

摘　　要：对山西省运城市投产桑园内桑树发生根部腐烂、枝叶萎凋枯死病害的病原菌进行分离鉴定,为病害的有效控制提供理论依据。从桑树发病植株根部分离到一株病原菌(暂命名为TY.GF1),将该病原菌接种到健康桑树根部,其致病症状与桑根腐病的症状相似。该病原菌在PDA培养基上的培养性状及孢子形态特征与米根霉(Rhizopus oryzae)相似。通过病原菌TY.GF1的核糖体18S rDNA及内部转录间隔区(ITS)序列PCR扩增和测序,分别获得长度为1 805、627 bp的序列片段。基于18S rDNA及ITS序列构建的进化树显示,与TY.GF1菌株亲缘关系最近的为米根霉和淀粉霉(Amylomyces rouxii)。结合病原菌致病性特点及形态特征与18S rDNA、ITS序列分析结果,初步鉴定这种新发生的桑树病害为桑根腐病,其病原菌可能为米根霉。The pathogens causing mulberry root rot disease and leaf withering disease in Yuncheng city of Shanxi province were isolated and identified to provide theoretical basis for effective prevention and control of these diseases.A pathogenic fungal strain,designated as TY.GF1,was isolated from diseased mulberry root and inoculated into healthy mulberry root.The resultant symptom was similar to that of mulberry rhizopus rot.Appearance and spore morphological characters of the pathogen cultured on potato dextrose agar（PDA） medium were similar to those of Rhizopus oryzae.PCR amplification and sequencing to its ribosomal 18S rDNA and internal transcribed spacer（ITS） yielded sequence fragments of 1 805 bp and 627 bp,respectively.The phylogenetic trees based on 18S rDNA and ITS sequences revealed that Rhizopus oryzae and Amylomyces rouxii had the closest genetic relationship with TY.GF1.Based on infectivity,morphological characters,and 18S rDNA and ITS sequencing results of the pathogen,the newly occurred mulberry disease was preliminarily identified as root rot disease of mulberry,and the pathogen was identified to be Rhizopus oryzae.

关 键 词：桑树病害 桑根腐病 米根霉 致病性 18SrDNA 内部转录间隔区 系统进化 

分 类 号：S888.71[农业科学—特种经济动物饲养]