Figure 8.

Effect of salt stress on the growth of wild-type (WT) and HbDHN transgenic A. thaliana seedlings. (A) Three-week-old seedlings were irrigated with 200 mM NaCl; relative electrolyte leakage, proline content, APX activity, SOD activity and catalase (CAT) activity in leaves were determined 12 h after treatment. Data represent means ± SE of three biological replicate samples. Different letters indicate a significant difference at the level of p < 0.05. Four columns in a block (WT and three transgenic lines) were analyzed for significant differences. (B) Two-week-old seedlings irrigated with 200 mM NaCl for 3 h; H₂O₂ and ${\text{O}}_2^{-}$ accumulation were indicated by DAB and NBT staining, respectively. Levels of blue and brown staining on leaves indicate the generation of ${\text{O}}_2^{-}$ and H₂O₂, respectively.