Demographic and random amplified polymorphic DNA analyses reveal high levels of genetic diversity in a clonal violet

We performed demographic and molecular investigations on woodland populatio ns of the clonal herb Viola riviniana in central Germany. We investigated t he pattern of seedling recruitment, the amount of genotypic (clonal) variat ion and the partitioning of genetic variation among and within populations. Our demographic study was carried out in six violet populations of differe nt ages and habitat conditions. Ii revealed that repeated seedling recruitm ent takes place in all of these populations, and that clonal propagation is accompanied by high ramet mortality. Our molecular investigations were per formed on a subset of three of these six violet populations. Random amplifi ed polymorphic DNA analyses using six primers yielded 45 scorable bands tha t were used to identify multilocus genotypes, i.e. putative clones. Consist ent with our demographic results and independent of population age, we foun d a large genotypic diversity with a mean proportion of distinguishable gen otypes of 0.93 and a mean Simpson's diversity index of 0.99. Using AMOVA we found a strong genetic differentiation among these violet populations with a Phi (ST), value of 0.41. We suggest that a high selfing rate, limited ge ne flow due to short seed dispersal distances and drift due to founder effe cts are responsible for this pattern. Although Viola riviniana is a clonal plant, traits associated with sexual reproduction rather than clonality per se are moulding the pattern of genetic variation in this species.