Osmotically Induced Water Stress, Potassium Uptake, and Stomatal Aperture in Epidermal Strips ofVicia fabaL.

Abstract

Uptake of potassium ions, estimated microdensitometrically, and stomatal opening in isolated epidermal strips from Vicia faba L. cv. Aquadulce were both inhibited by incubation of the strips in solutions of low solute potential. The inhibition of potassium uptake was substantially reduced by preincubation of the strips in benzylaminopurine¹ solution. The data are discussed in terms of the induction of abscisic acid synthesis by water stress in the epidermal strips and the antagonism to its effects by BAP.