Figure 1.

Loss-of-function mutation of prt6 enhanced tolerance to moderate (sublethal) salinity at the seed germination and seedling stages. (A) Dose-response of wild-type (WT) and prt6 seeds to NaCl during seed germination. Seeds were incubated under sublethal levels of NaCl (≤150 mM) for 4 d. (B) Time-course observation of seed germination in WT and prt6 seeds under sublethal salinity. Seeds were incubated under 100 mM NaCl for up to 5 d. (C) Photos of WT and prt6 seedlings that were grown upside down under non-stress or moderate salinity. Four-day-old seedlings grown under non-stress conditions were transferred on half-strength MS plates containing 0 or 150 mM NaCl and incubated upside down for 4 d. (D) Dose-response of WT and prt6 root growth to moderate salinity. Four-day-old seedlings were grown vertically on half-strength MS plates containing a range of NaCl concentrations for 4 d. Relative germination and root growth in (A), (B), and (D) were calculated by comparison to non-stressed WT or prt6. Data represent means ± SE [n = 3 in (A,B); n = 24 in (D)]. Asterisks indicate significant difference between WT and prt6 (* p < 0.05; *** p < 0.001).