Figure 6. Pre-treatment with 5-azaC alleviates differences in stress tolerance and methylation changes.

A. Twenty plants per each experimental group were germinated in half-MS medium. The plants of control group remained in this medium for the entire length of the experiment. At 3 dpg, the plants belonging to a ‘transfer’ group were transferred to similar half-MS medium and served as a ‘transfer’ control. At 3 dpg, the plants of the ‘5-AzaC’ group were transferred to 50 µM 5-azaC. At 3 dpg, the plants of the ‘5-AzaC/NaCl’ group were transferred to 50 µM 5-azaC, and at 8 dpg, they were transferred to 100 mM NaCl. At 8 dpg, the plants of the ‘NaCl’ group were transferred to 100 mM NaCl. All plants were harvested at 19 dpg, and genomic DNA was prepared and digested either with HpaII or MspI. The experiment was repeated three times. B. Twenty plants from Ct1, S1_25 and S1_75 groups were germinated on half-MS medium supplemented with or without 5-azaC and at the age of one week were moved to 0, 100, 150 and 200 mM NaCl. The experiment was repeated three times. C. Root length (the average of 3 independent plates, 20 plants per each plate, with s.e.m.). Asterisks show significant differences between the S1_25 and the C1 group and the S1_75 and the C1 groups (a single-factor ANOVA, p<0.05, for all groups). D. The data are shown as percentage of methylation related to the methylation level in the C1 plants of the control group. Significant differences between S1_25 and C1 for each group (p<0.05 in all cases) are labelled with asterisks.