Fig. 7.

Net fluxes of NH₄⁺ (A), K⁺ (B), and H⁺ (C). Arabidopsis Col-0 plants were grown on agarose plates with NO₃⁻ as nitrogen source and without K⁺ and NH₄⁺. Fluxes were measured for 5 min in bathing solution (0.1 mM CaCl₂) 15 min after the addition of various NH₄⁺, K⁺, TEA⁺, and Gd³⁺ as indicated.