It is still a risk to plant crops in the croplands with a low concentration of cadmium because of the high accumulation capacity of some leafy vegetables. In this study, water spinach was planted in four main soil series (Wa, Eh, Tk, and Yu) in Taiwan that were artificially spiked with Cd. The soil available content of phosphorous was raised to 10 to 15 mg/kg and the accumulation and chemical form of Cd were analyzed. Experiment results showed that the phosphorous addition in Wa and Eh could promote the growth of water spinach. The accumulation and upward translocation of Cd also increased in the treatment of phosphorus compared to the control. The addition of phosphorus increased the percentage Cd in FHAc which revealed that the mobility and toxicity of Cd were reduced in the treatment of phosphorus.
Keywords: cadmium, chemical form, crop safety, phosphorus, translocation