اثر برخی عوامل کلات کننده بر گیاه پالایی باقلا (Vicia faba) در یک خاک آلوده به کادمیوم.

Phytoremediation is an important method for refining heavy metals, but the main limitation is the low bioavailability of the metals. Chelating agents, by releasing heavy metals from the soil solid phase, can increase their uptake by the plants. In this research, the effects of some chelating agents on the phytoremediation of Vicia faba in a calcareous soil contaminated with Cd were investigated. A factorial experiment was conducted based on a completely randomized design with three replications in the greenhouse of Razi University. The factors included Cd at four levels (0, 5, 10, and 15 mg kg^-1 soil as CdCl2), and three chelating agents including ethylene di-amine tetra acetic acid (EDTA), citric acid (CA), and oxalic acid (OA), at two levels (4 and 8 mmol kg^-1 ). The results showed that the highest Cd concentration in the root and shoot (39.90 and 27 mg kg^-1, respectively) was obtained at 15 mg kg^-1 of Cd and 8 mmol kg^-1 of EDTA, CA, and OA. The highest values of transfer factor (0.67) and biological accumulation factor (5.65) were obtained at the highest level of Cd pollution and 8 mmol kg^-1 of chelating agents. This indicates that firstly, cadmium was mainly accumulated in the root and was less transferred to the shoot. Secondly, it shows the potential of bean in phytoremediation and Cd uptake. Also, the amounts of the measured factors with citric and oxalic acid were not much different from EDTA, and therefore, these two environmentally friendly natural chelating agents could be used instead of EDTA. [ABSTRACT FROM AUTHOR]