Population genetic structure of Satureja subspicata Bartl. ex Vis. (Lamiaceae) in central Dinaric Alps and its relevance for DNA barcoding strategies
Of the four species of the genus Satureja (Lamiaceae) that are recognized in Bosnia and Herzegovina, S. subspicata has the the widest distribution. It is taxonomically challenging species of geographically limited distribution and little data on its genetic diversity throughout its range is available. We sampled six geographically distinct populations from Bosnia and Herzegovina and applied nrDNA (ITS1, ITS2), chloroplast markers (matK and trnL) and AFLP to examine genetic diversity of S. subspicata in the center of its distribution range and to explore the possibility of establishing the species DNA barcode. AFLP analysis showed large genetic differentiation among populations as well as moderate correlation between genetic distance among populations and geographic distance among locations. MatK has not proven useful in distinguishing S. subspicata from sympatric species. However, nrDNA sequences provided necessary resolution power, with ITS2 being more informative. Estimates of evolutionary divergence between nrDNA sequences obtained in our research and homologous sequences of sympatric Satureja deposited in the GenBank reveal closer relationship between geographically proximate populations of different species and slight divergence within S. subspicata sequences pool. This outcome highlights the importance of considering overall genetic diversity across the distribution range of a species when assigning DNA barcode.