茶组植物种间关系的cpDNA、rDNA ITS和mtDNA序列分析

摘要

[Objective] DNA sequence analysis had provided a more convenient method for plant phylogenetic analysis,identification,classification and so on.[Method] 15 pairs of primer from the gene sequences of cpDNA,rDNA and mtDNA were designed,which were used to analyze the interspecific relationships of 16 tea germplasm resources which were collected from 5 species and 2 variants of tea plant.[Result]5 cpDNA primer pairs and 4 mtDNA primers were amplified and sequenced,3 rDNA ITS primers fail to be amplified in all accessions.There were 8 pairs of primer with mutation sites among all accessions were used to do DNA sequence analysis,and the result indicated that the longest sequence was 390F-1326R (859 bp),and the shortest one was orf25 (446 bp).The rbcla-rev had the most informative positions (24),and the nad4L/orf25 was just the opposition (2).Site variable ratio varied from 0.37 ％ (nad4L/orf25) to 4.76 ％ (rbcla-rev),and the average in cpDNA(2.91％) was much higher than that in mtDNA(0.55 ％);There were 9 variable sites within Camellia.sinensis var.sinensis,accounting for0.19 ％ of total loci,and 90 variable sites between different species,accounting for 1.85 ％ of total loci;8 sequences were spliced to construct molecular phylogenetic tree according to the MP method,in which 16 accessions were divided into 3 groups.[Conclusion] This study would provide useful references for the application of DNA sequence analysis in the tea plant.%[目的]DNA序列分析在物种系统进化、分类和鉴定等方面展示出了强大的生命力.[方法]本研究对来源于cpDNA、rD-NA ITS和mtDNA序列的15对引物在茶组植物的5种2变种共16份资源中进行了种间关系研究.[结果]在15对引物中,来自cpDNA的6对引物有5对完成了扩增与测序,来自rDNA ITS的3对引物均未得到单一目的片度,来自mtDNA序列的6对引物中,共有4对完成了扩增与测序.对在种间存在位点差异的8对引物序列比对:序列长度最长的为390F-1326R(859 bp),最短的为orf25(446 bp);品种间变异位点最多的为rbcla-rev(24个),最少的为nad4I/orf25(2个).位点变异率最高的为rbcla-rev(4.76％),最低为nad4L/orf25(0.37％),cpDNA的碱基变异率平均值(2.91％)要远高于mtDNA (0.55％);8对引物在茶变种内发生变异的位点共有9个,占总位点数的0.19％;不同变种间发生变异的位点有90个,占总位点数的1.85％;将8对引物测序得到的序列拼接,按照MP法构建了分子系统树,可以将参试的16份茶树资源分为3大类.[结论]本研究为DNA序列分析在茶组植物中的应用提供了参考.