E. Kliphuis

Cytotaxonomic Investigations in Some Angiosperms Collected in the Valley of Aosta and in Tre National Park « Gran Paradiso »

SUMMARYThe chromosome number of 53 species of Angiosperms, occurring in the Valley of Aosta and in the National Park « Gran Paradiso » was determined. Some notes on the taxonomy of some species are presented in this paper.

Chemotaxonomical investigations of theSymphytum officinale polyploid complex andS. asperum (Boraginaceae): The pyrrolizidine alkaloids

By means of thin layer chromatography in conjunction with mass spectrometry the pyrrolizidine alkaloid patterns derived fromSymphytum asperum, several cytotypes ofS. officinale agg. and the artificial hybrids of the former taxa, were compared. The obtained patterns were not essentially affected by variation in cytotype, harvesting times and -location of plants. Lycopsamine, acetyl-lycopsamine and symphytine or their isomers were generally found in theS. officinale cytotypes, echimidine and symphytine inS. asperum. The interspecific hybrids contained all alkaloids mentioned. The definite lack of echimidine in the 2 n=40 cytotype proves that it is conspecific withS. officinale and does not belong to a hybrid-swarmS. asperum × S. officinale with 2 n=48.

Chemotaxonomical investigations of theSymphytum officinale polyploid complex andS. asperum (Boraginaceae): Phytosterols and triterpenoids

From a comparison of phytosterol and triterpenoid patterns of severalSymphytum officinale cytotypes,S. asperum and their interspecific hybrids,S. ×uplandicum, which were obtained from thin layer chromatography and gaschromatography (also in combination with mass spectrometry), the hybrid character of the latter taxon is clearly shown. The specific value of the triterpenoid isobauerenol as a chemotaxonomical marker within this group is discussed in some detail.