摘要
分析辣椒属ITS序列，为辣椒属系统位置、进化关系提供分子生物学依据。以辣椒属（Capsicum）4个栽培种36份不同基因型辣椒种质资源为试材，对其rDNA转录间隔区（intemaltranscribedspacers，ITS）进行PCR扩增。扩增产物经纯化、克隆和测序后，获得ITS序列信息，随后利用MEGA5．05软件分析其序列特征，并探讨了辣椒属种质资源的系统进化关系。结果表明，辣椒属ITS基本序列全长656bp，G＋C含量57．47％。供试材料的ITS序列长度变异较大，ITSl、5．8S和ITS2区长度变异都有发生。序列比对表明，供试辣椒材料ITS区共有387个变异位点0TSl：153；5．8S：82；ITS2：152），信息位点322个，同源性为71．0％-100％，遗传分歧为0-0．3604。以烟草为外类群，将ITS1、5．8S和ITS2序列作为一个共同的数据矩阵进行系统发育树构建，辣椒属Gfrutescens和Cbaccatum种被单独分出，echinense和Cannuum种聚在一起，C．annuum与其他3个栽培种的亲缘关系由近至远分别是c．chine珊趴C．frutescens和c．baccatum，c．annuum种的32份供试材料主要分为3个分支6个亚分支，聚类分析结果与形态分类不能完全对应。
The phylogeny of pepper （Capsicum） was investigated by using ITS sequences and it will provide useful information for pepper classification and evolution. Thirty-six different genotype germplasm resources from four cultivated species in Capsicum were used as materials to amplify the ribosomal DNA internal transcribed spacer （ITS）. The amplified fragments were purified to be cloned and sequenced. Then sequences character and phylog- enetics relationship were analyzed using MEGA 5.05 software. The Results showed that the length of Capsicum ITS sequences was 656bp, and its G＋C content was 57.47%. There have a signification variation of the length of ITS in these materials, it occurred in ITS 1, 5.8S and ITS2. It has 387 variable sites in total （thereinto, ITS 1：153; 5.8S： 82; ITS2： 152）, and 322 parsim-info sites. The homology and genetic distances ranged from 71% to 100% and from 0 to 0.360 4, respectively. Using Nicotiana tabacurn as outgroup, ITS1, 5.8S and ITS2 sequences as a common data matrix was used to construct ofphylogenetic tree. C. frutescens and C. baccatum were divided firstly; C. chinense and C. annuum were clustered into one group. The results from cluster analysis showed that the genetic distances ofC. annuurn with other three species beginning with nearer were C. chinense, C. frutescens and C. baccatum. Three groups and six sub-groups were clustered by alignment analyses using the 32 accessions of C. annuum, and clustered results did not fully correspond to the current morphologic classification, suggestion that the genetic differences among those accessions ofC. annuurn could not be precisely reflected by the current taxonomic system.
出处
《分子植物育种》
CAS
CSCD
北大核心
2013年第6期795-803,共9页
Molecular Plant Breeding
基金
现代农业产业技术体系建设专项资金(CARS-25)
国家科技支撑计划项目(2012BAD02B02)
江苏省农业科技自主创新资金体系类项目(CX(12)1004)共同资助
