Identification of the genus Epimedium with DNA barcodes

The traditional identification for Epimedium is inadequate due to the morphological variation and complicated procedure. DNA barcoding is a new technique for species identification by a standard DNA region. However, there has been no consensus emerged for plant barcoding due to the low rates of evolution in plastid DNA. In this paper, we compared the performance of four candidate DNA regions (psbA-trnH, ITS, rbcL, matK) in ten species of Epimedium. To select a suitable barcode, ranking criteria included: the success efficiency of polymerase chain reaction (PCR) amplification and sequencing; genetic divergences; the barcoding gap. The psbA-trnH represented easy amplification, high level of interspecific divergence and well-separated barcoding gap. The other three loci (ITS, rbcL, matK) was inadequate for application. We concluded that the psbA-trnH region was the better potentially DNA barcode for the genus Epimedium.