Identifi cation of medical plants of 24 Ardisia species from China using the matK genetic marker

Background: Ardisia is a group of famous herbs in China, which has been used as medical plants for more than 900 years. However, the species from the genus are so analogous that it is diffi cult to discriminate them just by morphological characteristics. DNA barcoding is a new technique that uses a short and standard fragment of DNA sequences to identify species. Objective: Choose a suitable DNA marker to authenticate Ardisia species. Materials and Methods: Four markers (psbA-trnH, internal transcribed spacer 2 [ITS2], rbcL, matK) were tested on 54 samples of 24 species from genus Ardisia. The success rates of polymerase chain reaction amplifi cation and sequencing, differential intra- and inter-specifi c divergences, DNA barcoding gap and identifi cation effi ciency were used to evaluate the discrimination ability. Results: The results indicate that matK has the highest interspecifi c divergence and signifi cant differences between inter- and intra-specifi c divergences, whereas psbA-trnH, ITS2 and rbcL have much lower divergence values. Matk possessed the highest species identifi cation effi ciency at 98.1% by basic local alignment search tool 1 [BLAST1], method and 91.7% by the nearest distance method. Conclusion: The matK region is a promising DNA barcode for the genus Ardisia.