摘要
本文以来自国内外的20株白菜黑斑病菌及近源种为研究材料,进行了5.8SrDNA及其侧翼ITS区的克隆、测序、序列变异及遗传进化关系分析。黑斑病菌及其近源种真菌核糖体5.8SrDNA及其侧翼ITS区序列比对结果显示,不同种菌株ITS1比ITS2在碱基构成上有更大变异,而且ITS1的序列长度变异比ITS2的大;而种内虽然各菌株的寄主和地理来源不同,但ITS1和ITS2在长度上均没有变异,碱基构成上存在微小的变异。对该区序列的聚类分析表明,白菜黑斑病菌3个种芸薹链格孢Alternariabrassicae、甘蓝链格孢A.brassicicola和萝卜链格孢A.japonica虽然地理来源和寄主不同,但种内的不同菌株均在一个独立的聚类组中,种之间以及其和链格孢属内其它种在聚类关系上能明显分开,可基于该区进行黑斑病菌的分类鉴定。
5.8S rDNA and its flanking internal transcribed spacers (ITS 1 and ITS2) of 20 isolates belonging to Alternaria brassicae, A. brassicicola and A. japonica were cloned and sequenced employing the universal primers ITS4 and ITS5. Alignment analysis indicated that the length and the base composition of ITS 1 were more variable than that of ITS2 among the species. Whereas in any species no difference was shown in the length of ITS1 and ITS2. The base composition was shown faintly diverse. Phylogenetic analysis of ITS1 and ITS2 revealed that all of the strains in despite of being isolated from different locations and different hosts were strictly divided into three clades according to species. The results suggest that the ITS sequence could be used as taxonomic evidence for Alternaria spp,.
出处
《菌物学报》
CAS
CSCD
北大核心
2005年第3期414-421,共8页
Mycosystema
基金
国家"十五"科技攻关计划专题项目(编号2002BA516A08-11)部分内容