蒟蒻薯属(薯蓣科)植物DNA条形码研究  

Using DNA Barcoding in Genus Tacca(Dioscoreaceae)

作　　者：赵月梅[1,2] 张玲 

机构地区：[1]中国科学院西双版纳热带植物园,云南勐腊666303 [2]中国科学院研究生院,北京100049

出　　处：《植物分类与资源学报》2011年第6期674-682,共9页Plant Diversity

基　　金：中国科学院知识创新工程重要方向项目(KSCX2-YW-Z-0904);中国科学院大科学装置工程项目(2009-LSF-GBOWS-01)

摘　　要：蒟蒻薯属(Tacca)植物种间在形态上差别不大,导致分类上存在一定的困难。DNA条形码是一种利用短的DNA标准片段来鉴别和发现物种的方法。本研究利用核基因ITS片段和叶绿体基因trnH-psbA,rbcL,matK片段对蒟蒻薯属6个种的DNA条形码进行研究,对4个DNA片段可用性,种内种间变异,barcode gap进行了分析,采用Tree-based和BBA两种方法比较不同序列的鉴定能力。结果显示:单片段ITS正确鉴定率最高,片段组合rbcL+matK正确鉴定率最高。支持CBOL植物工作组推荐的条码组合rbcL+matK可作为蒟蒻薯属物种鉴定的标准条码,建议ITS片段作为候选条码。丝须蒟蒻薯Tacca integrifolia采自西藏的居群与马来西亚居群形成了2个不同的遗传分支,且两者在形态上也存在一定的差异,很可能是一个新种。Tacca （Dioscoreaceae） is a small genus which is taxonomically difficult because of a lack of obvious morphologically differences among species. DNA barcoding is a new method of rapid species identification and dis- covery using short, standardized genes or DNA regions. In this study, four candidate DNA barcoding regions that three （rbcL, matK, trnH-psbA） from chloroplast genome and one （ITS） from the nuclear genome, were evaluated among 36 accessions representing 6 species of Tacca. The capability of those regions were evaluated by intra- and in- ter-specific divergence and barcode gap analyses, and the identification efficiency was assessed using Tree-based and BBA methods. The results indicated that both ITS and the core barcode rbcL＋matK proposed by CBOL exhibited the highest resolution as a single and combined data respectively. Based on overall performance： matK＋rbcL can be considered as a potential barcode for identifying the species of Tacca, ITS can be used as a supplementary barcode. DNA barcoding revealed two distinct lineages of T. integrifolia distributed allopatrically in Tibet and Malaysia. And these two lineages with morphological variations may potentially represent new species.

关 键 词：蒟蒻薯属 DNA条形码 ITS MATK RBCL TRNH-PSBA 

分 类 号：Q943[生物学—植物学]