Figure 1.

Growth and developmental phenotypes of multiple T-DNA insertion knockout mutants of vacuolar NHX1, NHX2, NHX3, and NHX4 in Arabidopsis. Multiple-order knockout mutants have either three (nhx2/3/4, nhx1/3/4, nhx1/2/4, and nhx1/2/3) or four T-DNA insertions in each of the four vacuolar NHX-type cation/H⁺ antiporters, as shown above each plant image. The functional copy of the vacuolar NHX gene is shown below each image. A, Four-week-old plants grown under 16-h/8-h light/dark at 23°C before flowering. The rosette images were digitally extracted and made into a composite for comparison. B and C, Quantification of rosette diameter (B) and dry weight (C) of whole shoots. Different letters in B and C indicate significant differences using Tukey’s lsd test (P ≤ 0.05). Values are means ± sd (n = 12). WT, Wild type.