The Influence of the Ca2+/K+ Balance and Light Energy on Alkaloid Content and Parttioning in Datura stramonium

Abstract

The influence of a varying Ca²⁺/K⁺ balance on alkaloid production and accumulation in Datura stramonium var. tatula L. Torr. (thorn-apple) was examined. Plants were grown in culture on two different mineral media, that varied only in the proportions of the two cations. In addition, plants were cultured under two different light regimes to investigate a possible interaction between different ecophysiological parameters. When plants were grown under a higher light energy regime, more alkaloids accumulated in the plants during a certain stage of development, but also a higher proportion was found in fruits and seeds. This was associated with a lower alkaloid content in leaves and stems. The observed effect of the Ca²⁺/K⁺ balance on alkaloid content in the leaves, was affected by the different light regimes. An interpretation, including the possible influence on glutamine content, is put forward.