基于ITS与psbA-trnH序列的不同种源华重楼遗传多样性分析

Genetic Diversity Analysis of Paris polyphylla var.chinensis from Different Provenances Based on ITS and psbA-trnH Sequences

为研究华重楼种内遗传多样性,利用ITS与psbA-trnH序列引物对40个不同种源华重楼进行测序分析,使用MEGA 5.0软件构建系统发育树。结果显示,40个华重楼种源的ITS序列长度在634~635 bp之间,其中ITS1、5.8S和ITS2长度分别为241~242 bp、165 bp和228 bp,全长含有变异位点21个;psbA-trnH序列长度在1024~1044 bp之间,全长含有变异位点33个。ITS序列下的种源遗传距离在0~0.0142之间,平均遗传距离为0.0034;psbA-trnH序列下种源遗传距离在0~0.0127之间,平均遗传距离为0.0023。聚类结果表明,ITS序列下不同种源的华重楼亲缘关系与其地理分布存在一定的相关性,但在psbA-trnH序列下相关性不明显。研究表明,不同种源华重楼的ITS序列的遗传多样性较为丰富,ITS序列较psbA-trnH序列更适于华重楼种内遗传多样性研究。本研究为华重楼种内分子鉴定与遗传多样性分析提供了理论依据。

In order to study the genetic diversity of different provenances of Paris polyphylla var.chinensis,40 provenances of P.polyphylla var.chinensis were sequenced and analyzed using ITS and psbA-trnH sequence primers,and a phylogenetic tree was constructed using MEGA 5.0 software.The results showed as followings:the total lengths of ITS sequences were 634 bp and 635 bp,the lengths of three fragments of ITS1,5.8S and ITS2 were 241~242 bp,165 bp and 228 bp,respectively,and there were 21 variable sites among the sequences;however,the total lengths of psbA-trnH sequence were between 1024 and 1044 bp and contained 33 variable sites.The genetic distance of the ITS sequence among different provenances was between 0 and 0.0142,and its average genetic distance is 0.0034;while,the genetic distance of psbA-trnH sequence was between 0 and 0.0127,and its average genetic distance was 0.0023.The clustering results showed that the genetic relationship of P.polyphylla var.chinensis among different provenances had some correlation with its geographical distribution under the ITS sequence to a certain degree,however,there was no obvious correlation under the psbA-trnH sequences.The results also showed that the genetic diversity of the ITS sequencesamong different provenances was relatively richer than psbA-trnH,and the ITS sequence was more suitable for the study of genetic diversity within the P.polyphylla var.chinensis species.Therefore,the results provide a theoretical basis for the molecular identification and genetic diversity analysis of P.polyphylla var.chinensis.