Figure 3.

The fresh weight and chlorophyll content under Zn²⁺ or Cd²⁺ stress. (a) Fresh weight of the WT and transgenic lines under Zn²⁺ at different concentrations. (b) Fresh weight of the WT and transgenic lines under Cd²⁺ stress at different concentrations. (c) Chlorophyll content of the WT and transgenic lines under Zn²⁺ Cd²⁺ stress at different concentrations. (d) Chlorophyll content of the WT and transgenic lines Cd²⁺ stress at different concentrations. WT: Wild-type tobacco. N13, N14, N24: Three homozygous transgenic tobacco lines (T₂). The 4−week−old WT and transgenic plants were treated under Zn²⁺ (0, 300, or 900 mg/kg) or Cd²⁺ (0, 100, or 200 mg/kg) for 3 weeks, respectively. Asterisks indicate a significant difference between transgenic lines and WT (*, p < 0.05; **, p < 0.01).