DNA Barcoding of Acer palmatum (Aceraceae)

Acer palmatum Thunb. (Aceraceae) is an important garden ornamental tree species in northern temperate regions. It is relatively difficult to classify by traditional methods due to frequent intraspecific hybridization and introgression. However, the emergence and development of DNA barcoding methods has provided an alternative approach to this issue. In this study, five candidate DNA noncoding regions (rpl16, psbA-trnH, trnL-trnF, rbcL and matK) from the chloroplast genome and internal transcribed spacer (ITS) region from the nuclear genome were used to distinguish eight taxa of A. palmatum. The identification efficiency estimated by PWG-distance and Tree-Building methods showed that single chloroplast DNA fragment (0% - 25%) or ITS fragment (12.5%) always showed low levels of species discrimination, while the combination of chloroplast DNA fragments (0% - 62.5%) and chloroplast DNA fragments plus ITS fragments (12.5% - 50%) had higher resolution for identifying A. palmatum. The highest discrimination rate of rpl16 + psbA-trnH + trnL-trnF reached 62.5%. Thus, we concluded that rpl16 + psbA-trnH + trnL-trnF could be considered as a potential barcode for taxa identification in A. palmatum.