The concentration of elements in the central vacuole sap and endosperm tissue during embryogenesis (Clivia miniata Regel)

Abstract

Changes in the concentration of eight elements (K, Na, Ca, Mg, Fe, Mn, Zn, Cu) in the central vacuole sap and endosperm tissue during development of Clivia miniata ovules using atomic absorption spectrometry were determined. Generally, the concentration of most of the elements in the central vacuole sap first increased to a certain maximum and then decreased (proembryo stage). In the endosperm tissue (proper embryo stage) the concentration of elements showed either a tendency to increase (K, Ca, Mg, Fe, Zn, Cu) or no visible change (Na, Mn) during embryogenesis. The concentration of the investigated elements (except Ca) was distinctly higher in the endosperm tissue than in the central vacuole sap. It is suggested that the elements contained in the sap were selectively taken up by the developing endosperm tissue and embryo. The final conclusion is that such selectivity leads to a gradual increase in the concentrations of these elements from the lowest in the central vacuole sap, medium in the endosperm tissue, to the highest concentration in the developing embryo.