Clonal diversity and subpopulation structure in central European relict populations of Saxifraga paniculata MILL. (Saxifragaceae)

摘要

Saxifraga paniculata is a rate and endangered glacial relict in central Europe. It shows high clonal reproduction. In this study, we analysed the clonal diversity and the subpopulation structure of three populations from the species main distributionarea in Germany outside of the Alps (Swabian Alb, Black Forest, Nahe Mountains). We used RAPD analysis to detect the genetic variation in S. paniculata and found high levels of clonal diversity. The percentage of distinguishable genotypes (PD) within populations of S. paniculata was 1.0 and even spatially well defined mats of rosettes consisted of several genotypes. In a cluster analysis, the investigated populations were clearly separated from each other. However, we detected no genetic differentiationamong subpopulations. We ascribe the high level of geno-typic variability to the species' mixed mating system, which creates and maintains high levels of genetic diversity within the populations of S. paniculata. Clonal reproduction seems, meanwhile, tobe of secondary importance for the propagation of the species.