茄子绒菌斑病2种斑型病原菌的比较  

Pathogen Comparison of 2 Eggplant Leaf spots Caused by Passalora nattrassii

作　　者：刘志恒[1] 郑川[1] 郭英伟 唐爽爽[1] 鲁迪[1] 王海宁[1] 

机构地区：[1]沈阳农业大学植物保护学院,沈阳110161 [2]本溪市林业种苗管理站,辽宁本溪117000

出　　处：《沈阳农业大学学报》2014年第2期147-151,共5页Journal of Shenyang Agricultural University

摘　　要：由灰毛茄钉孢(Passalora nattrassii)引起的茄子绒菌斑病是辽宁省近年来茄子设施栽培生产上趋重发生的叶部病害。该病害常见症状是霉层较密的小病斑———小斑型,本研究首次发现病斑较大、轮纹状霉层的新症状———轮斑型。通过比较2种斑型病原菌的形态和致病性,并进行rDNA-ITS序列分析,与黄枝孢(Cladosporium fulvum)进行比较,结果表明:分离自2种斑型的病菌,形态特征基本一致,但二者在分生孢子大小和细胞数目比例上有所不同,Z9菌丝生长速率略小于Z6,且Z6中3细胞的分生孢子居多,而Z9中4细胞的分生孢子居多;经人工接种茄子叶片后,叶片背面均产生了棕褐色霉层,与田间自然发病植株症状一致;供试2种斑型菌株的rDNA-ITS基因序列与GenBank中已登录的Passalora nattrassii序列相似性均达到99%,与番茄叶霉病菌序列的同源性仅为90%,且与黄枝孢在分生孢子大小和细胞数目上存在明显差异,可见,茄子绒菌斑病菌并非番茄叶霉病菌。据此,鉴定茄子绒菌斑病的致病菌为灰毛茄钉孢[Passalora nattrassii(Deighton)U.Braun&Crous]。Eggplant leaf spot infected by Passalora nattrassii has been a more and more seriously leaf disease in Liaoning Province in recent years. In addition to small spot-commom dense mold, the author for the first time discovered a new type spot-annular bigger mold on the leaves in the field. Pathogen identification was tested according to morphological characteristics, Koch＇s postulates and molecular biology, and comparison between Passalora nattrassii with CIadosporium fulvum. The results showed that： the pathogen from the two spots were almost the same in morphological characteristics, but they were slightly different from each other in the size and cell number of conidia, the mycelial growth rate of Z9 was slightly less than that of Z6 mycelial, and there were 3 more cells than other cells in Z6 spores while there were 4 more cells than other cells in Z9 spores. The stems showed symptoms of brown mold on the underside of leaves after inoculated with the pathogen, which was consistent with the symptoms of the natural infected plants. Identity of isolate Z6 （small spot） and Z9 （annular spot） were confirmed by analysis of the rDNA-ITS sequences with primer ITS1/ITS4. BLAST searches showed that both isolates were 99% identity with Passalora nattrassii on GenBank,but they were only 90% identity with Cladosporium fulvum. Passalora nattrassii was significantly different from Cladosporium fulvum in the size and cell number of conidia, the pathogen of eggplant leaf spot was not the one of tomato leaf spot which was previously believed. Therefore, the pathogen of two types of eggplant leaf mold was both identified as[Passalora nattrassii （Deighton） U. Braun ＆ Crous].

关 键 词：茄子绒菌斑病 灰毛茄钉孢 鉴定 致病性 rDNA-ITS序列 

分 类 号：S436.411[农业科学—农业昆虫与害虫防治]