EFFECTS OF CADMIUM ON MINERAL NUTRIENT CONCENTRATIONS IN PLANTS DIFFERING IN TOLERANCE FOR CADMIUM

The effects of 3 d treatments with 0.3 and 1.0 mg . L(-1) of cadmium ( Cd) on selected mineral nutrient composition in plants differing in to lerance for Cd were studied. The concentrations of potassium (K) decre ased in Cd-sensitive kidney bean and pea and that of manganese (Mn) de creased in the semiresistant rice and maize plants with increasing app lication of Cd in the culture solution. Copper (Cu) content increased in the roots of the plants above, but no changes in Cu contents were o bserved in the d resistant cucumber and pumpkin plants. Calcium(Ca), m agnesium (Mg), and zinc (Zn) did not show any clear tendency with Cd a pplications in any of the plants examined. Water absorption by kidney bean was reduced by Cd, but that of rice and cucumber was not. Permeab ility of the plasma membrane of root cells may be affected by Cd, wher eas absorption of some of the elements and water may be prevented.