Effects of root and foliar treatments with lead, cadmium, and copper on the uptake distribution and growth of radish plants

Abstract

The effects of treatment of radish plants with cadmium, lead, and copper were studied. Both root treatment and foliar treatment were used. All three elements were found to inhibit the growth of radish plants. Cadmium and lead were greater growth inhibitors than copper on the plant. Effects of cadmium and copper were greater on the growth of shoots, while the effect of lead was greater on the growth of roots. Foliar treatment was more harmful to plant growth than root treatment. The uptake of metal ions and the distribution of this uptake in the roots and shoots of treated plants were determined. Cadmium and copper uptake by plant was concentrated mostly in the shoots, while the uptake of lead was concentrated more in the roots of treated radish plants. The amount of metal uptake increased with the increase in metal ion used in treatment of plants. The amount of uptake was higher in foliar-treated plants than in root-treated plants. Concentration of cadmium and lead exceeded the maximum allowed limit in foods in most cases; concentration of copper exceeded the maximum allowed limit in food only in one sample. The percentage of metal ions taken up by plants from the total amount of metal ions added during treatment was very small. This percentage was comparatively higher in the case of foliar treatment than in the case of root treatment. It was also higher from solutions having low concentrations of metal ions than from solutions having high concentrations of metal ions.