Electrostatic association and donnan phenomena as mechanisms of ion accumulation

Excised roots of barley (Hordeum vulgare, var. Campana) were incubated for periods up to 24 hours in salt solutions of various concentrations and ion accumulation was determined at various time intervals. The data were consistent with the existence of 2 components of ion uptake, one accounting for ion uptake from solutions below 1 mm and both components contributing to uptake from solutions of concentrations higher than 1 mm.