Chemische Verteidigung der Lupinen: Zur biologischen Bedeutung der Chinolizidinalkaloide

Quinolizidine alkaloids deter the feeding of herbivores (mammals, insects, molluscs), inhibit the growth and the development of bacteria and fungi and inhibit the germination of grass seeds and lettuce. Half-maximal inhibitor concentrations fall in the range between 0.5 and 15mM (= 0.01–0.3%). The actual concentrations of lupin alkaloids in the plant are between 5–200mmol/kg, i.e. much higher than the inhibitory concentrations. Since alkaloid-free lupins have a higher incidence of herbivory and disease, we assume that the biological function of lupin alkaloids is chemical defense besides minor roles as nitrogen transport and nitrogen storage compounds.

Teil der Habilitationsschrift (Wink 1984c). — Vorgetragen auf der Tagung der Deutschen Botanischen Gesellschaft, Wien, September 1984.     

Inseln: Ursprung der Vielfalt

The theory of island biogeography was originally developed to evaluate the influence of island size and distance from mainland on their number and composition of species. Meanwhile, this theory has become an important tool for nature conservation strategies. Due to various reasons, organisms arriving at islands are tending along their evolution to develop dwarf of giant forms. Although islands are constantly emerging and decaying, they are representing a constant phenomenon on earth, and therefore have a particular importance for evolutionary processes. Today, genetic analyses have archived importance in the disentanglement of colonisation processes of islands. Furthermore, islands often represent localities with high proportions of endemic species, which are increasingly threatened through the invasion of alien species.