应用PCR产物直接测序法分析了繁缕〔Stellaria media(L.)Villars〕及其近缘种和鹅肠菜〔Myosoton aquaticum(L.)Moench〕的ITS和trnL-F序列的碱基差异,并以孩儿参〔Pseudostellaria heterophylla(Miq.)Pax〕为外类群构建N-J系统树,分析了这些种类的种间亲缘关系。结果表明,供试的繁缕属(Stellaria L.)种类及鹅肠菜的ITS和trnL-F序列长度分别为521~784和788~951 bp,各有变异位点77和59个,其中信息位点分别为18和11个,种间碱基差异百分率分别为6.5%和3.1%。ITS的碱基组成为A22.1%、T20.9%、G28.5%和C28.5%,G+C含量57.0%;trnL-F的碱基组成为A 35.9%、T33.7%、G 15.7%和C 14.8%,G+C含量30.5%。繁缕、雀舌草(S. alsine Grimm)和箐姑草(S. vestita Kurz)的ITS和trnL-F序列一致;鹅肠菜的ITS序列中有4个位点与前述种类不同,但trnL-F序列则相同;中国繁缕(S. chinensis Regel)的ITS和trnL-F序列与孩儿参较相似。在N-J系统树中,鹅肠菜与繁缕、雀舌草和箐姑草聚为一支,表明它们的亲缘关系相对较近,支持将鹅肠菜重新归入繁缕属的分类处理。研究结果显示,ITS和trnL-F序列分析均可用于繁缕及其近缘种的鉴别,且ITS是更为适宜的分子标记。

The trnL-F and ITS sequence differences of Stellaria media (L.) Villars and its related species as well as Myosoton aquaticum (L.) Moench were determined by PCR direct sequencing, and N-J treewas constructed using Pseudostellaria heterophylla (Miq.) Pax as an outgroup to analyze the interspecific relationship. The results show that the length of ITS and trnL-F is 521- 784 and 788- 951bp, with 77 and 59 variable sites, 18 and 11 information sites, respectively. And the percentage of base differences of ITS and trnL-F sequences among different speciesis 6. 5% and 3. 1%, respectively. The nucleotide composition of ITS is 22.1%A,  20.9% T, 28.5% G and 28.5%C, with the G+C content of 57.0%. The nucleotide composition of trnL-F is 35.9%A,  33.7%T, 15.7%G and 14.8% C, with the G+C content of 30.5%. S. media, S. alsine Grimm and S. vestita Kurzhave the same ITS and trnL-F sequences. The ITS sequence of M. aquaticum is differentin 4 sites with the above three species, while its trnL-F sequence is the same. The ITS and trnL-F sequences of S. chinensis Regel are similar tothose of P. heterophylla. M. aquaticum, S. media, S. alsine and S. vestita cluster to gether in N-J phylogenetic tree, indicating arelatively close relationship, which supports the suggestion of putting M. aquaticum back into Stellaria L. It is concluded that ITS and trnL-F markers can be used in identification of S. media and its related species, and ITS is a better molecula rmarker.