Figure 6.

sos3–1 hkt1–1 accumulates less Na⁺ and maintains intracellular K⁺ relative to sos3–1 in medium supplemented with NaCl. Col-0 wild-type (SOS3 HKT1) or sos3–1 or sos3–1 hkt1–1 seedlings (3 weeks old) were transferred to liquid medium and grown for 2 days. An aliquot of 5 M NaCl stock solution was then added into the flask to supplement the medium with 100 mM NaCl. An equivalent volume of H₂O was added to cultures that were not supplemented with NaCl. Illustrated are the mean values ± SE (n = 3) for Na⁺ (A) or K⁺ (B) content as determined by atomic absorption spectrophotometry or for intracellular K⁺/Na⁺ ratio calculated from the data in A and B (C). Data from one of two experiments with similar results are shown.