The effect of the heavy metal cadmium on the glutathione transferase (GT) activity was studied in the shoots and roots of wheat and pea seedlings. The exposure to cadmium led to the reduction of plant growth rates and to a marked induction of GT activity in both plants. In wheat the induction was stronger in the roots than in the shoots at low cadmium concentrations (40-160 microM), but at 640 microM cadmium the effect was more pronounced in the shoots (4.0-fold increase of the activity as compared to control). In pea seedlings the induction rates were generally higher in the roots than in the shoots (at 640 microM cadmium the activity in the roots was 340% of the control).