Further observations on the physico-biochemical and physiolo gical gradients in the ovule during embryogenesis

Abstract

In the developing ovule (Clivia sp. and Clivia miniata; exponential phase of embryo growth) the following gradients were found: of osmotic value, concentration of free amino acids, respiration rate in the endosperm tissue, and osmotic value and respiration rate gradients in the embryo. Generally these gradients (with the exception of respiration rate in the embryo) were directed from the chalaza to the micropyde i.e. in the opposite direction of the embryo elongation (imicropyle→chalaza). The obtained results suggest of the direction of some gradients can change during the ovule development.