The study of genetic variation and phylogenetic relationship of "Thach Hoc" local orchild species using matk gene

Abstract

Dendrobium genus has been widely used as herbal plants in China and India. Because of their important roles as ornamental plants and medical drugs, the identification of this genus becomes essential for their preservation. This genus has been classified and analyzed by many DNA barcoding markers such as ITS, ITS2, rbcL or matK. In this study, phylogenetic analysis using the maturase-coding gene matK was applied to determine genetic variation and phylogenetic relationship of 6 local Vietnamese Dendrobium species collected from Bidoup National Park – Nui Ba, Lam Dong province. In the study, 6 local Dendrobium samples sequences were amplified by conventional PCR and sequenced by Sanger sequencing. They were then compared with 24 others Dendrobium species taken from NCBI. The phylogenetic tree was constructed by Neighbor-joining (NJ) method. The data were analyzed by MEGA 6. The data showed that the number of variables as well as genetic distance of Dendrobium aphyllum (Roxb.) C. Fisher (DA) was the highest among 6 samples. Both Dendrobium aphyllum (Roxb.) C. Fisher (DA) and Dendrobium crumenatum SW. (DC), contain specific insertion sites and they form a new group compared with the others. KeyWords: Dendrobium, Dendrobium aphyllum (Roxb.) C. Fisher, Dendrobium crumenatum SW., matK, phylogeny