[Influence of nitrogen compounds and of auxin on embryogenesis in tissue cultures].

Investigations of a regularly reacting system for the analysis of embryo formation in tissue cultures of Daucus carota led to new points of view about this process and to the clarification of controversial results. Essential factors for the embryogenesis are the nitrogen and the auxin of the nutrient. Inorganic (KNO3, NH4NO3) as well as organic (amino acids, amides) nitrogenous compounds enhance the embryo formation; glutamine and ammonium nitrate are especially efficient. Auxin (2,4-D), on the other hand, has an inhibiting effect. Both factors obviously influence each other, i.e. under appropriate experimental conditions the relation between the amount of nitrogen and that of auxin in the medium determines whether embryogenesis in vitro occurs. The bearing of these results upon different questions is discussed.