XVI International Botanical Congess

Data based on enzyme electrophoresis of ten European taxa of Viola subsection Viola suggest a polyploid origin of the group. All taxa have distinct multilocus phenotypes except Viola alba sspp. Alba and scotophylla, which are identical. No variations found among nine populations of V. collina and variation levels within other taxa are low. Hybridization seems extensive but putative F1 hybrids are distinctly less fertile than the parental species. Nevertheless, increased fertility of later generation hybrids and band sharing patterns among taxa indicate an important role of hybridization and introgression in past and present evolution within the subsection.