DNA barcoding in closely related species:A case study of Primula L.sect.Proliferae Pax(Primulaceae) in China  

作　　者：Hai-Fei YAN Gang HAO Chi-Ming HU Xue-Jun GE 

机构地区：[1]Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China [2]College of Life Sciences, South China Agricultural University, Guangzhou 510642, China

出　　处：《Journal of Systematics and Evolution》2011年第3期225-236,共12页植物分类学报（英文版）

基　　金：supported by the Research Fund for the Large-scale Scientific Facilities of the Chinese Academy of Sciences(2009-LSFGBOWS-01);Major Innovation Program of the Chinese Academy of Sciences(KSCX2-YW-N-0807);the National Natural Science Foundation of China(Grant Nos.30870171,30900160)

摘　　要：DNA barcoding is a method of identifying species by analyzing one or a few short standardized DNA sequences. There are particular challenges in barcoding plants, especially for distinguishing closely related species. Hence, there is an urgent need to evaluate the performance of candidate loci for distinguishing between species, especially closely related species, to complement the rbcL ＋ matK combination suggested as the core barcode for land plants. We sampled 48 individuals representing 12 species in Primula sect. Proliferae Pax in China to evaluate the performance of eight leading candidate barcode loci （matK, rbcL, rpoB, rpoC1, trnH-psb.4, psbK-psbI, atpF- atpH, and internal transcribed spacer （ITS））. The core combination rbcL ＋ matK gave only 50% species resolution in sect. Proliferae. In terms ofintraspecies and interspecies divergence, degree of monophyly, and sequence similarity, ITS, trnH-psbA, and psbK-psbI showed good performance as single-locus barcodes. Internal transcribed spacer displayed the highest genetic divergence and best discriminatory power, both alone and in combination with rbcL ＋ matK （83.3% species resolution）. We recommend evaluating the use of ITS for barcoding in other species. Low or single copy nuclear regions would provide more sophisticated barcoding tools in the long term, even though further research is required to find suitable loci.DNA barcoding is a method of identifying species by analyzing one or a few short standardized DNA sequences. There are particular challenges in barcoding plants, especially for distinguishing closely related species. Hence, there is an urgent need to evaluate the performance of candidate loci for distinguishing between species, especially closely related species, to complement the rbcL ＋ matK combination suggested as the core barcode for land plants. We sampled 48 individuals representing 12 species in Primula sect. Proliferae Pax in China to evaluate the performance of eight leading candidate barcode loci （matK, rbcL, rpoB, rpoC1, trnH-psb.4, psbK-psbI, atpF- atpH, and internal transcribed spacer （ITS））. The core combination rbcL ＋ matK gave only 50% species resolution in sect. Proliferae. In terms ofintraspecies and interspecies divergence, degree of monophyly, and sequence similarity, ITS, trnH-psbA, and psbK-psbI showed good performance as single-locus barcodes. Internal transcribed spacer displayed the highest genetic divergence and best discriminatory power, both alone and in combination with rbcL ＋ matK （83.3% species resolution）. We recommend evaluating the use of ITS for barcoding in other species. Low or single copy nuclear regions would provide more sophisticated barcoding tools in the long term, even though further research is required to find suitable loci.

关 键 词：DNA barcoding ITS plastid candidates Primlula sect. Proliferae species discrimination. 

分 类 号：Q523[生物学—生物化学] TP391.44[自动化与计算机技术—计算机应用技术]