Figure 5.

Compromised growth of T. salsuginea TsHKT-RNAi lines under K⁺-limiting conditions. A to C, T. salsuginea seedlings harboring either the vector control (Ts WT) or the TsHKT-RNAi construct (lines 77-1 and 81-2) were grown on 1/2 MS for 10 d and transferred to 1/2 MS control medium (A), K⁺-deficient medium (B), or the same medium supplemented with 10 mm KCl (C). The K⁺-deficient medium was modified from MS medium containing no KNO₃ and with KH₂PO₄ replaced with (NH₄)₂HPO₄ (see “Materials and Methods”; Supplemental Table S2). Photographs were taken after incubation in a vertical position for 15 d. D, The root growth in C is quantified. E, Arabidopsis wild type (WT) and athkt1 knockout mutants under K⁺-limiting conditions. Arabidopsis Col-gl1 wild-type plants and Arabidopsis plants harboring different alleles of athkt1 knockout mutants (athkt1-1, -3, and -4) were grown on 1/2 MS for 4 d and transferred to K⁺-deficient medium supplemented with 10 mm KCl. The photograph was taken after the transferred seedlings had been incubated in a vertical position for 15 d. F, The root growth in E is quantified. Error bars in D and F represent sd values of three repeats (n = 30). Bars = 10 mm in A, B, C, and E. [See online article for color version of this figure.]