Figure 5.

Overexpression of SbWRKY22 in transgenic Arabidopsis shows improved tolerance to Al stress. (A) Reverse transcription polymerase chain reaction characterization of SbWRKY22 expression in complimented lines and overexpression lines. (B) The Al-sensitive phenotype of WT (Col-0), Atwrky54 mutant, and the transgenic lines. Five-day-old seedlings were precultured on a solid MS medium at pH 5.8, then transferred to a solid medium containing 1 mM CaCl₂ and 1% (w/v) sucrose at pH 4.5, with or without 50 μM AlCl₃ for 5 d. Scale bar, 1 cm. (C) Relative root elongation (root elongation with Al treatment/root elongation without Al treatment) of WT and transgenic lines. Data are shown as means with SD (n ≥ 20). Columns with different letters indicate significant differences between plants according to Tukey’s test (p < 0.05). Experiments were repeated three times.