DETERMINATION OF CHANGES IN NUTRITIONAL ELEMENTS AND ANTIOXIDANT AMOUNTS IN THE PLANT BY APPLICATION OF HEAVY METALS (Cu, Pb, Cd) TO CORN PLANT (Zea mays L.)

Excess of some heavy metals as copper lead and cadmium are significant contaminants for agricultural soils, and they affect plant life cycles by changing their defense enzymes and mineral element contents. This study was aimed to determine the effects of copper, lead and cadmium (Cu, Pb, and Cd) on the mineral concentration and antioxidant, enzymes activities in root and leaves of corn. They changed mineral elements content in roots and leaves of plants. Cd and Pb levels increased depending on applied doses in growth medium. Pb and Cd treatment showed harmful effect by limiting uptake of nutrients to the roots. Cu application increased ascorbate peroxidase (APX), catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) activities in the plant roots; whereas Pb increased APX activity and Cd increased both SOD and APX activities. Their applications decreased enzyme activities in leaves compared to control. This study showed that Cd has limited the level of calcium, copper, iron, magnesium, manganese, and zinc in roots. Pb induced the uptake of calcium, magnesium, and zinc in leaves.