Effect of EDDS Chelate on Increasing Cd Phytoremediation Efficiency by Corn (Maxima Cv) in a Soil Treated with Municipal Waste Compost (A Case Study: Khomein Municipal Waste Compost)

In recently years, plant-assistant bioremediation is preferred to the other methods and causes increasing of remediation efficiency. Among this, applying chelating such as Ethylenediamine disuccinic acid (EDDS) can probably affect soil heavy metal availability that increase phytoremediation efficiency. Thus, this research was conducted to evaluate the effectiveness of EDDS chelate on corn (Maxima CV) Cadmium uptake in a soil treated with Arak municipal waste compost. A factorial experiment with a randomized complete block design with 3 factors in three replications was conducted in greenhouse conditions. Treatments were consisted of applying Arak municipal waste compost (0. 15 and 30 t ha-1) , soil polluted cadmium (0, 20, 30 and 40 mg Cd kg soil-1) from Cd(NO3)2 sources and applying EDDS chelate (0 and 1.5 mmol kg soil-1). After 60days, soil physic-chemical properties and root and shoot cadmium concentration was measured. Applying 1.5 mmol kg soil-1 EDDS chelate in a Cd polluted soil (40 mg Cd kg soil-1) without receiving Arak municipal waste compost caused a significant increasing in Cd availability by 21 percent, while applying 1.5 mmol kg soil-1 EDDS chelate in a Cd polluted soil (40 mg Cd kg soil-1) with receiving 30 t ha-1 Arak municipal waste compost increased the Cd availability by 10 percent. The EDDS chelate effectiveness was affected by soil organic matter, as, with increasing the amount of Arak municipal waste compost, the effectiveness of applying EDDS chelate was decreased. The similar results for root and shoot Cd concentration confirm this matter clearly.