Changes in the cellular permeability of the embryonic axis inGcer arietinum L. seeds during germination

Abstract
The effect of short chain fatty acids on the cellular permeability of embryonic axis inGcer arietinum seeds was studied. Octanoic (OCT) and nonanoic (NON) adds, which reduce both germination and growth of the embryonic axis and raise the inhibitor effects of the supraoptimal temperatures (30‡C), induce a greater ionic efflux into the medium (conductivity). NON reduces glucose (3-0-MG) and K+ (86Rb) uptake during the germinative process, this action being counteracted by fusicoccin (FC) at optimal (25‡C) and supraoptimal temperatures (30 ‡C). Tonoplast and plasmalemma increase their permeability to the K+ efflux when NON is present. Addition of NON+FC gives rise to higher values in the efflux rate, the vacuolar compartment being the most affected. Temperatures around zero (2 ‡C) notably reduce the isotope efflux from cytosol and vacuole. NON acid does not significantly affect the efflux of3H-ABA, suggesting that it does not cause any important changes in the phytohormone compartmentation.