Data from: Evaluation of 11 single-locus and seven multilocus DNA barcodes in Lamium L. (Lamiaceae)

The aim of this work was to evaluate the suitability of selected DNA regions in the barcoding of plants, based on the species belonging to the genus Lamium (Lamiaceae). For this purpose, nine chloroplast barcodes, that is, accD, matK, rbcL, rpoA, rpoB, rpoC1, rpoC2, trnH-psbA, trnL-trnF, as well as ITS nuclear region, and intron of mitochondrial nad5 gene were tested. Among the single-locus barcodes, most effective in the identification of Lamium species was the trnH-psbA spacer and matK gene. The high level of variability and resolving power was also observed in the case of rpoA and rpoC2 genes. Despite the high interspecies variability of ITS region, it turned out to be inapplicable in Lamium identification. An important disadvantage of ITS as a barcode is a limitation of its use in polyploid plants, samples contaminated with fungal material or samples with partially degraded DNA. We have also evaluated five-two-locus and two-three-locus barcode regions created from a combination of most effective single loci. The best-performing barcode combinations were matK + trnH-psbA and matK + rpoA. Both of them had equally high discriminative power to identify Lamium species.

本研究旨在以唇形科野芝麻属（Lamium）物种为研究类群，评估所选DNA区域在植物DNA条形码（DNA barcoding）鉴定中的适用性。为此，本研究共测试了9个叶绿体DNA条形码（chloroplast barcodes）区域，即accD、matK、rbcL、rpoA、rpoB、rpoC1、rpoC2、trnH-psbA、trnL-trnF，以及核基因组内部转录间隔区（Internal Transcribed Spacer，ITS）与线粒体nad5基因内含子。在单一位点DNA条形码中，对野芝麻属物种鉴定效果最佳的为trnH-psbA间隔区与matK基因。rpoA与rpoC2基因同样表现出较高的序列变异性与物种分辨能力。尽管ITS区域的种间变异水平较高，但却不适用于野芝麻属的物种鉴定。作为DNA条形码，ITS的应用存在显著局限：无法用于多倍体植物、受真菌污染的样本，或是DNA部分降解的样本。本研究还评估了由高效单一位点条形码组合而成的5组双位点与2组三位点条形码区域。表现最优的条形码组合为matK + trnH-psbA与matK + rpoA，二者对野芝麻属物种均具备极高的物种分辨能力。