DNA barcoding and molecular systematics in genus Coelogyne Lindl. (Orchidaceae)

Subtribe Coelogyninae (Epidendroideae, Orchidaceae) comprises 16 genera, including Coelogyne Lindl. The aim of this study was to reveal the sectional relationships, and relations to the genus Pholidota, using DNA bar coding. This technique helps the identification of species even if only a small piece of material is available. In the present study, the DNA barcode was based on rbcL, the Rubisco large sub unitfrom the chloroplast genome. The inter-specific divergence values and species discrimination rates were calculated by Kimura 2 parameter (K2P) using MEGA 4.0. The rbcL with average interspecific divergence values yielded 72.72% species resolution, and could distinguish all the species of Coelogyne and Pholidota investigated. Invariably the genus Pholidota shows a close affinity with Coelogyne. This supports the inclusion of the genus Pholidota in the subtribe Coelogyninae of tribe Coelogyneae.