title: Promise and Challenge of DNA Barcoding in Venus Slipper (Paphiopedilum).
abstract: Orchidaceae are one of the largest families of flowering plants, with over 27,000 species described and all orchids are listed in CITES. Moreover, the seedlings of orchid species from the same genus are similar. The objective of DNA barcoding is rapid, accurate, and automated species identification, which may be used to identify illegally traded endangered species from vegetative specimens of Paphiopedilum (Venus slipper), a flagship group for plant conservation with high ornamental and commercial values. Here, we selected eight chloroplast barcodes and nrITS to evaluate their suitability in Venus slippers. The results indicate that all tested barcodes had no barcoding gap and the core plant barcodes showed low resolution for the identification of Venus slippers (18.86%). Of the single-locus barcodes, nrITS is the most efficient for the species identification of the genus (52.27%), whereas matK + atpF-atpH is the most efficient multi-locus combination (28.97%). Therefore, we recommend the combination of matK + atpF-atpH + ITS as a barcode for Venus slippers. Furthermore, there is an upper limit of resolution of the candidate barcodes, and only half of the taxa with multiple samples were identified successfully. The low efficiency of these candidate barcodes in Venus slippers may be caused by relatively recent speciation, the upper limit of the barcodes, and/or the sampling density. Although the discriminatory power is relatively low, DNA barcoding may be a promising tool to identify species involved in illegal trade, which has broad applications and is valuable for orchid conservation.
authors.affiliation: Shenzhen Key Laboratory for Orchid Conservation and Utilization, The National Orchid Conservation Center of China and The Orchid Conservation and Research Center of Shenzhen, Shenzhen, China.|Center for Biotechnology and BioMedicine, Graduate School at Shenzhen, Tsinghua University, Shenzhen, China.|State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Guo
authors.affiliation: Center for Biotechnology and BioMedicine, Graduate School at Shenzhen, Tsinghua University, Shenzhen, China.
authors.forename: Lai-Qiang
authors.initials: LQ
authors.lastname: Huang
authors.affiliation: Shenzhen Key Laboratory for Orchid Conservation and Utilization, The National Orchid Conservation Center of China and The Orchid Conservation and Research Center of Shenzhen, Shenzhen, China.
authors.forename: Zhong-Jian
authors.initials: ZJ
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
authors.forename: Xiao-Quan
authors.initials: XQ
authors.lastname: Wang
mesh_terms: D058893:DNA Barcoding, Taxonomic / Q000379:methods*; D018742:DNA, Chloroplast / Q000235:genetics*; D021901:DNA, Intergenic / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics*; D017343:Genes, Plant; D014644:Genetic Variation; D006239:Haplotypes; D029595:Orchidaceae / Q000235:genetics*; D010802:Phylogeny; D015203:Reproducibility of Results; D013045:Species Specificity
chemical_list: D018742:DNA, Chloroplast; D021901:DNA, Intergenic; D018744:DNA, Plant