A comparative assessment of the resolving power of chloroplast (rbcL, psbA-trnH, matK) and nuclear (ITS1, ITS2) molecular markers for species identification of representatives of the genus Betula was performed. It was shown that chloroplast sequences are characterized by low variability, with the poorest performance obtained for rbcL. In contrast, markers of the ITS region possess significantly higher discriminatory power. ITS2 demonstrated potential for the identification of ten species (ranging from 61.7 to 93.1 %), whereas the best performance was revealed for ITS1: the highest number of reliably identified species (five species with 100 % efficiency and eleven above 65 %), the barcoding index reached its maximum among all markers studied (6.04), and the proportion of overlapping intra- and interspecific variability pairs was the lowest (26.66 %). Taken together, the data support ITS1 as the most reliable molecular marker for identification of species of the genus Betula.

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