title: Evaluation of the DNA barcodes in Dendrobium (Orchidaceae) from mainland Asia.
abstract: DNA barcoding has been proposed to be one of the most promising tools for accurate and rapid identification of taxa. However, few publications have evaluated the efficiency of DNA barcoding for the large genera of flowering plants. Dendrobium, one of the largest genera of flowering plants, contains many species that are important in horticulture, medicine and biodiversity conservation. Besides, Dendrobium is a notoriously difficult group to identify. DNA barcoding was expected to be a supplementary means for species identification, conservation and future studies in Dendrobium. We assessed the power of 11 candidate barcodes on the basis of 1,698 accessions of 184 Dendrobium species obtained primarily from mainland Asia. Our results indicated that five single barcodes, i.e., ITS, ITS2, matK, rbcL and trnH-psbA, can be easily amplified and sequenced with the currently established primers. Four barcodes, ITS, ITS2, ITS+matK, and ITS2+matK, have distinct barcoding gaps. ITS+matK was the optimal barcode based on all evaluation methods. Furthermore, the efficiency of ITS+matK was verified in four other large genera including Ficus, Lysimachia, Paphiopedilum, and Pedicularis in this study. Therefore, we tentatively recommend the combination of ITS+matK as a core DNA barcode for large flowering plant genera.
authors.affiliation: State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, P. R. China.
authors.forename: Songzhi
authors.initials: S
authors.lastname: Xu
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan 650201, China.
authors.forename: Dezhu
authors.initials: D
authors.lastname: Li
authors.affiliation: Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun Township, Mengla County, Yunnan 666303, China.
authors.forename: Jianwu
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, P. R. China.
authors.forename: Xiaoguo
authors.initials: X
authors.lastname: Xiang
authors.affiliation: State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, P. R. China.
authors.forename: Weitao
authors.initials: W
authors.lastname: Jin
authors.affiliation: Shanghai Chenshan Botanical Garden, Chenhua Road 3888, Songjiang, Shanghai 201602, China.
authors.forename: Weichang
authors.initials: W
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, P. R. China.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Jin
authors.affiliation: National Resource Centre for Chinese Material Medica, China Academy of Chinese Medical Science, Beijing 100700, China.
authors.forename: Luqi
authors.initials: L
authors.lastname: Huang
mesh_terms: D001208:Asia; D058893:DNA Barcoding, Taxonomic; D021901:DNA, Intergenic; D018744:DNA, Plant; D031667:Dendrobium / Q000145:classification* / Q000235:genetics*; D019143:Evolution, Molecular; D017343:Genes, Plant; D014644:Genetic Variation; D010802:Phylogeny; D017422:Sequence Analysis, DNA
chemical_list: D021901:DNA, Intergenic; D018744:DNA, Plant