Figure 1. Nutritional and cultivar comparisons of NaCl-stimulated K⁺ efflux.

Cultivar differences in ⁴²K⁺ efflux from roots of intact rice (Oryza sativa L. cvs. ‘IR29’, ‘IR72’, and ‘Pokkali’) in response to sudden provision (at t  =  15.5 min, see arrow) of 160 mM NaCl. Seedlings were grown and tested in a full nutrient medium supplemented with either 0.1 (A – D) or 1.5 mM K⁺ (E – H), and one of four N regimes: 0.1 mM NH₄ ⁺ (A, E), 0.1 mM NO₃ ⁻ (B, F), 10 mM NH₄ ⁺ (C, G), and 10 mM NO₃ ⁻ (D, H). Error bars indicate ± SEM.