Fig. 4. Soil total metal concentrations at the beginning of the experiment (T₀) and at harvest. Shown values are the means and standard error of 10 replicate pots (at harvest one sample was taken per pot after soil homogenization). Note: if error bars are not visible they were too small to be plotted. WT, wild-type Indian mustard; APS, adenosine triphosphate sulfurylase–overexpressing Indian mustard; GS, glutathione synthetase–overexpressing Indian mustard; -ECS, -glutamylcysteine synthetase–overexpressing Indian mustard. The letters above the bars indicate statistically significant groups (t test, compairing each pair, = 0.05).