The perspectives for DNA barcoding of Rhaponticum carthamoides (Willd.) Iljin using rbcL gene sequence

The methods of biological species identification using nucleotide sequences of short genome regions (DNA barcoding) are actively developed. The universal DNA barcode for plants remains to be discovered, and one of the leading candidates is the plastid gene of the large subunit of ribulose-bisphosphate carboxylase gene ( rbcL ). In our study, we estimated the part of rbcL gene as a possible marker for molecular identification of Rhaponticum carthamoides (Willd.) Iljin. Due to its officinal properties, the species is susceptible to uncontrolled and illegal harvesting from natural populations. Today, the species needs to be protected and therefore is included into the Red Data Books of the Russian Federation and certain regions. The study was carried out using plants from the natural populations sampled from the Khamar-Daban Ridge (South Siberia) and considering now as Rh. carthamoides var. chamarense (Peschkova) O S Zhirova. It was shown that rbcL gene can be used to identify Rh. carthamoides at least from the populations of the Khamar-Daban Ridge using a fragment of the maximum length or its 3’ region. Apparently, the 5’ region of the gene ( rbcL a) most often used as DNA barcode for plants may be of lesser importance for Rh. carthamoides . The rbcL gene sequences can be also used for the development of approaches for Rh. carthamoides identification in the medicinal preparations and products containing dried tissues to prevent their falsification and illegal harvesting of this species. The combination of rbcL gene with additional markers seems to be highly desirable to create effective DNA barcodes for Rhaponticum species.