An Anomaly in Potassium Accumulation by Barley Roots

Abstract

When excised barley roots were incubated in 0.01 to 0.1 mm KCl solutions containing 0.2 mm CaSO₄, there was a peak in the K⁺ accumulation against concentration curve at 0.02 to 0.04 mm KCl. The peak in the K⁺ accumulation curve was shifted to lower K⁺ concentrations when Ca²⁺ concentration was decreased and to higher K⁺ concentrations when Ca²⁺ concentration was increased. Increasing Ca²⁺ concentration in the treatment solution was observed to be stimulatory, inhibitory, or neutral depending on the K⁺ concentration.