【摘要】 测定了山羊草属 (Aegilops)二倍体物种核rDNAITS区序列 ,发现其碱基数介于 6 0 1～ 6 0 7之间 ,比报道的小麦族 (Triticeae)其他属的ITS区序列略长 ;G +C含量达 6 1.1%～ 6 2 .9% ,序列间的分化距离为 0 .0 0 5 0～ 0 .0 46 8。用PHYLIP 3.5c软件包对所测得的DNA数据进行聚类分析 ,结果显示 :1.Ae .speltoides与该组其他种相距很远 ,支持将其从Sitopsis组中独立出来 ;2 .Ae.uniaristata不与同组的另两个物种聚在一起 ,却与Ae.caudata和Ae .umbellulata的关系很近 ,与以前对该属的细胞遗传学研究结果相似。更多还原

【Abstract】 The entire sequences of the ITS region of nuclear rDNA were determined from 9 diploid species in the genus Aegilops of Poaceae by direct double_sequencing. These sequences, together with the published ITS sequences, were analyzed using PHYLIP 3.5c package to assess the phylogenetic relationships in the genus Aegilops. The ITS regions and the coding region of 5.8S rDNA analyzed in the study were ranged from 601 to 607 bp in length, among them 75 variable sites were observed. The G+C content being, 61.1%-62.9%, is similar to most other species in Poaceae. The phylogenetic analysis of ITS sequences showed that there was no sister group relationships between Ae. speltoides and the other species of Section Sitopsis, thus suggesting that Ae. speltoides could be separated from the section. The phylogenetic trees also indicated that Ae.uniaristata in Section Comopyrum was more closely related to Ae.caudata and Ae.umbellulata than to the other members in this section, which was in general agreement with the previous cytogenetic results.更多还原