Chloroplast DNA variation ofTilia cordata(Tiliaceae)

The distribution of haplotypic diversity of 17 Tilia cordata Mill. populations was investigated by PCR–RFLP markers of the chloroplast genomes. A high number of haplotypes (14) and high total genetic diversity (h T = 0.881) were detected. The distribution of the chloroplast DNA haplotypes revealed low geographic structure of the genetic diversity; the coefficient of differentiation between populations, G st = 0.552, was lower than the mean value reported for maternally inherited markers in Angiosperm tree species. The value of population subdivision for ordered alleles, as measured by N st , was significantly higher than the value of population subdivision for unordered alleles (N st = 0.662, G st = 0.552), thus indicating the presence of a phylogeographic structure. The relatively low genetic differentiation among T. cordata populations may be explained mainly as a consequence of human impact on this species.