砂仁茎枯病病原菌的分离与鉴定  

Isolation and Identification of Stem Blight Pathogen on Amomum villosum

作　　者：刘威[1] 蒋妮[1] 叶云峰[1] 刘丽辉[1] 胡凤云[1] 林伟[1] 

机构地区：[1]广西壮族自治区药用植物园,广西药用资源保护与遗传改良重点实验室,广西南宁530023

出　　处：《贵州农业科学》2014年第11期127-129,共3页Guizhou Agricultural Sciences

基　　金：南宁市科学研究与技术开发计划项目"广西砂仁规范化技术研究及示范推广"(桂科攻:201002051C)

摘　　要：为明确砂仁茎枯病病原菌的分类地位,对该病原菌进行分离培养,通过致病性测定、病原菌形态特征观察及rDNA-ITS序列分析对病原菌进行鉴定。结果表明：砂仁茎枯病主要危害茎秆,初染病时病斑呈水渍状,逐渐扩大为纺锤形至不规则形,病斑边缘黄褐色,病健部分界明显,病斑上着生小黑点,后期病斑部质脆,呈灰褐色至灰白色干枯,导致茎部易折断,地上部分枯萎;分生孢子团奶油状,培养6～7d后产生菌核;分生孢子盘圆形,直径60～150μm,分生孢子梗栅栏状排列,基部褐色,向顶渐淡,具隔膜,分生孢子单个顶生,单胞,纺缍形,两端顶部钝圆,（10～18）μm×（4.5～5）μm,附着孢大量,具钝齿状裂片;分子生物学鉴定所得rDNA的ITS序列与GenBank中多个Colletotrichum crassipes菌株ITS序列的同源性最高,相似度为99%。引起砂仁茎枯病的病原鉴定为壳皮炭疽菌（Colletotrichum crassipes）。To ascertain the taxonomic status of the pathogen of stem blight on A.villosum,the pathogen was isolated and its pathogenicity,morphology and rDNA-ITS sequence were analyzed in this study.The results showed that stem blight mainly damaged the stem.Water soaked lesions initially appeared at the stem,and then extended to spindle or irregular,with brown and clear edge.Lesions with conidia on the surface late got brittle,grey-brown to pale and caused stem broken and plant wilt.Conidia mission looked like cream and produced sclerotium when cultivated for 6～7days.Acervulus was rounded with the diameter of 60～150μm.The conidia with brown base and septate were arranged like barrier.It is a single cell,fusiform,and measured 10～18μm× 4.5～5μm.In molecular identification,the rDNAITS sequence of the pathogen showed 99% homology with several sequences of Colletotrichum crassipes.According to the morphological and molecular characteristics,the pathogen was identified as C.crassipes.

关 键 词：砂仁 茎枯病 病原鉴定 壳皮炭疽菌 

分 类 号：S435.67[农业科学—农业昆虫与害虫防治]