半夏属药用植物trnL-F序列与种间遗传关系分析

Analysis of Sequencing of trnL-F and Interspecific Genetic Relationship of Medicinal Species in Pinellia

为了给半夏属物种鉴别和种间遗传关系分析提供分子佐证,对中国半夏属植物5个种共9份材料的trnL-F进行克隆测序,用ClustalX1.81,PAUP4.0软件进行序列分析,采用邻接法(Neighbor-Joining,N-J)构建系统发育树。结果表明所测物种的序列全长1027～1136bp,G+C含量34.6%～36.8%,经排序并两端切平后,序列长994bp,当空位始终做缺失处理时,产物有29个变异位点,6个信息位点。聚类结果显示,半夏属物种总体聚为2大分支,虎掌为1个分支,另外8份材料:滴水珠、盾叶半夏、石蜘蛛以及半夏聚为1个分支。采用邻接法得到的9份半夏属药用植物的分子系统树有一定的差异,表明这9份半夏属药用植物的物种分化不完全,序列进化不一致,是物种鉴别的有效分子标记。

The aims were to identify some closely related Pinellia species and evaluate interspecific relationships among them.The cpDNA trnL-F sequence of 9 taxa representing 5 species of Pinellia and Philodendron sp.Schott as one outgroup were determined by clone and sequencing,and the sequences were analyzed by means of the software of ClustalX1.81 and PAUP 4.0.The length of trnL-F sequence was 1027-1136 bp,the percentage of G ＋C content was 34.6%-36.8%.The length became to 994 bp after aligned these sequences and cut the overhanging terminals.When the gaps were always treated as missing,there were twenty nine variable sites and 6 parsim-info sites,which could be used to identify some species of Pinellia.Based on the results of cluster,the Pinellia species could be divided into two major branches.P.inlegrifolia,P.ternata,P.cordata and P.peltata were clustered into branch Ⅰ,while P.pedatisecta was in branch Ⅱ.The molecular phylogenetic trees of these nine Pinellia species constructed by N-J methods were considerable discrepant.It suggested that species differentiations of these nine medicinal taxa in Pinellia were incomplete and the evolution of trnL-F sequence was not identical,which were good molecular markers for identification species of Pinellia.