Zhao Y, Li Y, Liu Y, Yang Y F
Key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland Science, Northeast Normal University.
Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.
Genet Mol Res. 2015 Mar 13;14(1):1903-10. doi: 10.4238/2015.March.13.19.
Ixiolirion is a genus of unresolved taxonomy. DNA barcoding is a technique that allows species identification using standardized DNA sequences. In this study, a total of 23 individuals, representing 2 Chinese Ixiolirion species, were sampled to test the effectiveness of 3 DNA barcodes [internal transcribed spacer (ITS), chloroplast tRNA intron, and megakaryocyte-associated tyrosine kinase] for species identification. Of the 3 DNA barcodes, ITS displayed the maximum level of polymerase chain reaction and sequencing success as well as the highest sequence variation. Intra-specific sequence distances of ITS, chloroplast tRNA intron, and megakaryocyte-associated tyrosine kinase were 0, 0, and 0-0.1%, respectively, with 8.3, 0.6, and 0.5% as mean inter-specific distances, respectively. All individuals of each species formed a monophyletic group (clade) in the neighbor-joining trees constructed using the 3 single-DNA barcodes. Our results demonstrated that ITS, chloroplast tRNA intron, and megakaryocyte-associated tyrosine kinase DNA markers could be used to identify Ixiolirion species. Our results indicate that DNA barcoding provides a reliable and effective means for discriminating Ixiolirion species, and is a robust tool for resolving taxonomic controversies of Ixiolirion in combination with morphology-based taxonomy.
鸢尾蒜属是一个分类地位未明的属。DNA条形码技术是一种利用标准化DNA序列进行物种鉴定的技术。在本研究中，共采集了代表2个中国鸢尾蒜属物种的23个个体，以测试3种DNA条形码[内转录间隔区（ITS）、叶绿体tRNA内含子和巨核细胞相关酪氨酸激酶]在物种鉴定中的有效性。在这3种DNA条形码中，ITS显示出最高的聚合酶链反应和测序成功率以及最高的序列变异。ITS、叶绿体tRNA内含子和巨核细胞相关酪氨酸激酶的种内序列距离分别为0、0和0 - 0.1%，平均种间距离分别为8.3%、0.6%和0.5%。在使用这3种单DNA条形码构建的邻接树中，每个物种的所有个体都形成了一个单系类群（分支）。我们的结果表明，ITS、叶绿体tRNA内含子和巨核细胞相关酪氨酸激酶DNA标记可用于鉴定鸢尾蒜属物种。我们的结果表明，DNA条形码为区分鸢尾蒜属物种提供了一种可靠且有效的手段，并且是一种结合基于形态学的分类学来解决鸢尾蒜属分类学争议的有力工具。
