Figure 1.

Viability of the PR and the LR during lethal salinity. Seven day old WT Arabidopsis seedlings were subjected to salt stress (200 mM NaCl + 1/2 MS) for 12, 24, 48 and 72 h and then stained with FDA + PI. Shown are representative confocal images of: (a and b) WT plants stained with FDA + PI in the PR and LR positions. The presented confocal images were captured after 48 hours of stress. Scale bars = 50 µm. (c and d) Graphical display of the confocal images presented in (a) and (b) during 0, 12, 24 and 72 hours of salt stress. The colored lines in the graphs indicate LR lengths (in µm). The experiments were repeated three times (n = 20 plants in each time point in all the experiment ± S.E.). Statistical analysis was done by Tukey’s Honest Significant Difference test (at P < 0.05) for each time point separately. (Significant differences are indicated by small letters). The shown images are projection of the entire z-stack at maximum intensity. The complete Z stack of the individual of the presented images can be found in Figs. SI1, SI2. Confocal images of non-stressed plants can be found in Fig. SI3.