河南小麦黑胚病优势病原菌及其近似种rDNA-ITS序列分析  

rDNA-ITS Sequence Analysis of the Dominant Pathogens of Wheat Black Point Alternaria spp. in Henan and their Similar Species

作　　者：郜瑞敏[1] 袁虹霞[1] 邢小萍[1] 张猛[1] 代君丽[1] 于巧丽[1] 李洪连[1] 

机构地区：[1]河南农业大学植物保护学院,郑州450002

出　　处：《农业生物技术学报》2010年第3期445-455,共11页Journal of Agricultural Biotechnology

基　　金：国家粮食丰产科技工程河南课题(2006BAD02A07-1);中国科学院知识创新工程重大项目(KSCX1-YW-09)共同资助

摘　　要：从河南省具有地域代表性的5个不同地区分离小麦黑胚病原菌Alternaria spp.菌株17株,经形态鉴定主要为链格孢属两个近似种A.alternata和A.tenuissima。通过与GenBank中登录的链格孢属中的9个种的rDNA-ITS序列比较分析,发现所有供分析菌株具有很高的同源性,其中与6个小孢子种A.alternata、A.tenuissima、A.mali、A.gaisen、A.citri、A.arborescens同源性为98%～100%,在聚类图上成为一支,而3个大孢子种A.radicina、A.porri和A.solani聚为另外一支,可明显地与其它小孢子种区分开。通过对Al-ternaria58个菌株的rDNAITS序列分析发现,同一个种或相似种内不分地域范围和寄主都有很高的保守性。与小孢子种相比,3个大孢子种在位点97-171、365-402、443-490处具有各自的特异位点,所以这些序列有可能作为它们分类鉴定、分子标记及系统发育的重要依据。分析结果表明,ITS1-5.8S-ITS2序列分析只能验证小麦黑胚病菌形态学鉴定的结果,但不能用于链格孢近似种的分类鉴定。17 isolates of Alternaria spp. which is the dominant pathogens of wheat black point were collected from five different places in Henan. There are two similar small-spored species A. alternate and A. tenuissima with the morphological identification. Compared with the rDNA-ITS sequence of 9 species of Alternaria＇s sequence from GenBank, the result shows that all the isolates have high homology and the homology of the 6 small-spored species A. alternata, A. tenuissima, A. mali, A. gaisen, A. citri and A. arborescens is 98%～100%. But the three large-spored species A. radicina, A. porri and A. solani are separated from the 6 small-spored species clearly. Ac cording to the sequence analysis of 58 isolates in Alternaria spp., the isolates of the same or similar species have high conservation no matter the host or region. Compared with the small-spored species, 3 large-spored species have special base mutations in the site of 97-171、365-402、443-490. Thus, these special sequences can be important evidence in the classification, identification, molecular marker and phylogenetic analyse of some certain species. The results indicate that rDNA ITS1-5.8S-ITS2 sequence analysis can prove the morphological result of the pathogens of wheat black point, but it can not be used in the classification of the similar species of Alternaria spp..

关 键 词：小麦黑胚病菌 链格孢 RDNA-ITS 同源性 序列分析 

分 类 号：S763.15[农业科学—森林保护学]