Comparative molecular and phytochemical investigation of Leontodon autumnalis (Asteraceae, Lactuceae) populations from Central Europe.

Previous analyses of Leontodon autumnalis L. revealed the existence of two chemotypes. In the current study molecular and phytochemical methods were combined to investigate 24 Central European populations of L. autumnalis. The focus of this study was the correlation of molecular and phytochemical characters at the intraspecific level. DNA fingerprint profiles of 183 individuals were obtained by random amplified polymorphic DNA (RAPD) providing 77 molecular markers. Contents of phenolics and sesquiterpenoids of flowering heads and sub-aerial parts were quantified by HPLC-DAD analyses. HPLC results were evaluated by principal component analysis. Geographic distribution of the two detected chemotypes partially overlapped. Phylogenetic groupings displayed in an unrooted neighbor-joining tree calculated from the RAPD data matrix were correlated with the geographical origin of the plant material. However, genetic profiles neither correlated with the two chemotypes nor with the morphologically based subspecies of L. autumnalis recognized by some authors. The presented data imply that the morphotypes are of multiple origins or due to different ecological growing conditions rather than genetically determined and that phytochemical races are induced by a limited number of genetical differences, which might have occurred independently in different lineages of the L. autumnalis group.