Inhibition by abscisic acid of the light and dark uptake of potassium by slices of Vicia faba leaves

Abstract

Abscisic acid at a concentration of 10 mg/liter inhibits up to 79% of the potassium uptake of slices of expanding Vicia faba leaves in the dark, and up to 75% of the greater potassium influx occurring in the light. Abscisic acid has no effect on the potassium influx into tissue from non-expanding, mature leaves which consistently leak potassium into the media. The possible role of abscisic acid in ion movement within plant tissue is discussed.