Influence of Cadmium on Growth of Root Vegetable and Accumulation of Cadmium in the Edible Root

The problem of farmland contaminated by heavy metals raises serious concerns because the contaminants accumulated in the plant not only affect the growth and quality of crops but also threaten the health of consumers.In this research, three root vegetables, i.e., sweet potato (Ipomoea batatas L.), carrot (Daucas carota L.) and radish (Raphanus sativus L.), were planted in soil collected from cadmium-contaminated and uncontaminated farmland. The plant growth rate were used to investigate the influence of cadmium on the growth of these plants. The accumulation of cadmium in the edible root is also studied in order to understand the safety of these edible vegetables.The results indicate that during the initial growth period, cadmium does not show obvious influence on the growth of all three plants. When the edible root started to develop, the growth rate for plants growing in the contaminated soil is obviously affected. Their average mass is reduced by about 50%. The cadmium contents in the edible root of all three plants exceed the allowable quantities stipulated by various nations. Thus, the plants grown in cadmium-contaminated should be banned as foodstuff.