Figure 2.

ALA formation rate in four Arabidopsis hy1, hy2, gun1-1, and gun4-1 mutants. The ALA formation rate was determined in the leaves of 7-day-old seedlings grown on 0.5× MS medium supplemented with 1% (w/v) sucrose and given in% of the corresponding wild-type Ler-0 (light gray, 11 pmol ALA mg fw⁻¹ h⁻¹) or Col-0 (dark gray, 20 pmol ALA mg fw⁻¹ h⁻¹), respectively. Data are means of at least three biological replica ± SD. * Indicates a significant difference from wild-type at a level of P < 0.05.