Figure 6.

High-affinity K⁺ (Rb⁺) uptake in wheat roots in response to K⁺ deprivation. High-affinity uptake was suppressed in roots grown in 1 mm KCl. In K⁺-depleted roots grown hydroponically in H₂O or in 1 mm CaCl₂, high-affinity Rb⁺ uptake was induced. Average uptake rates from 10 (CaCl₂) or 3 (H₂O) replicate experiments are illustrated. The [Rb⁺] was 10 μm. FW, Fresh weight.