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分析了老芒麦和垂穗披碱草rDNA-ITS序列,为这两个种的鉴别提供分子指纹图谱,为系统发育提供分子生物学依据。结果表明,22份材料的ITS、ITS1、5.8S、ITS2序列长度均相同,依次为604bp、222bp、164bp、218bp,GC含量依次为62.25%～63.08%,62.16%～63.06%,59.76%,64.22%～65.60%。除5.8S外,碱基位点都有不同程度的变化,一些变异位点有明显的种性变异规律,可作为老芒麦和垂穗披碱草种质DNA指纹特异鉴别位点。7个ITS序列的同源性98.7%～99.8%,遗传分歧0.2～1.3,具有保守性,为非近期分化类群。系统发育分析表明不同来源地的同种材料,差异主要表现在DNA变化快慢及碱基替换数,但相同的种归为一类,进一步反映了种内的遗传稳定性。
The rDNA-ITS sequences of Elymus sibiricus and Elymus natans were analyzed to provide molecular fingerprinting for the identification of these two species and to provide a molecular biological basis for phylogeny. The results showed that the lengths of ITS, ITS1, 5.8S and ITS2 sequences were the same in 22 accessions, followed by 604bp, 222bp, 164bp and 218bp, respectively. The GC contents of 62, 63.66, 63.76, 59.76, % ~ 65.60%. In addition to the 5.8S, the base sites have varying degrees of change, some of the variation sites have significant variation of species can be used as Simaia old wheat and Elymus racemosa DNA fingerprinting specific identification sites. The homologies of 7 ITS sequences ranged from 98.7% to 99.8% with genetic divergences from 0.2 to 1.3, which were conservative and non-recently differentiated. Phylogenetic analysis shows that the same species from different sources, the difference is mainly reflected in the DNA changes in the speed and the number of base substitutions, but the same species grouped together, further reflecting the intraspecific genetic stability.