基于ITS技术的11个茶花品种遗传多样性分析

Genetic Diversities from 11 Camellia Cultivars Based on ITS Approach

为了探索温州特色山茶花品种遗传多样性,采用核糖体转录间隔区（internal translation spacer,ITS）序列分析技术,对11个样品基因组DNA进行了ITS-PCR扩增、多重序列比对及种系发生等研究。结果表明,11个样品所扩增的ITS序列位于640~668bp之间（含ITS1、5.8S、ITS2）,而且具有较高的序列一致性和位点多态性;基于N-J（邻接法）和ME（最小进化法）（MEGA5.0,Bootstrap,1000）所构建的种系发生树表明：11个样品中,样品＇十景牡丹＇单独成支,其余10个样品聚类一起;在10样品分支中,2个样品（＇粉丹＇和＇六角大红＇）形成1个亚分支,其余8个样品形成另1个亚分支。本研究显示：11个样品中,＇十景牡丹＇遗传距离最远,＇粉丹＇和＇六角大红＇遗传距离次之,而其余8个样品遗传关系比较近（其中,样品＇复色倚阑娇＇与＇立春八宝＇＇、狮子笑＇＇、无暇玉＇＇、粉霞＇、＇大东方亮＇、＇玛瑙＇＇、胭脂莲＇等样品遗传距离依次降低）;两种种系发生树（N-J、ME树）树型结构高度一致,揭示了所构建的种系发生树比较接近11个样品间的真实遗传关系。

In order to investigate genetic diversities of 11 representative Camellia cultivars in Wenzhou,the author performed the ITS-PCR（internal translation spacer,ITS）,multiple sequence alignment and phylogenesis analyses.The results represented that：the sizes of amplified ITS sequences from 11 samples were between 640 bp and 668 bp（including ITS1,5.8S and ITS2） with high sequence identities and polymorphism.Based on NJ and ME analyses（MEGA 5.0 software;Bootstrap,1000）,phylogenetic tree from 11 samples showed that 10 samples clustered together while sample Shijing MD isolated alone.In 10 samples clade,two samples（Fendan and Liujiao DH） clustered closely and formed one subclade while other 8 samples did another.The results disclosed that：among 11 samples,Shijing MD had biggest genetic distance,2 samples（Fendan and Liujiao DH） did second,while other 8 samples had relatively close genetic relationships.Of these 8 samples,sample Fuse YLJ had more and more close genetic relationships with Lichun BB,Shizi X,Wuxia Y,Fenxia,Dadong FL,Manao,Yanzhi L,respectively.The tree structure from N-J was highly agreement with that from ME,which implied the phylogenetic tree could really reveal relationships among 11 samples.