مقايسه آثار افزودن اسيد سيتريك و كي ليت هاي مصنوعي بر افزايش پالايش گياهي كادميوم از خاك

Comparison Effects of Citric Acid and Synthetic Chelators In Enhancing Phytoremediation of Cadmium

Abstract In this study, the effects of enhancing synthetic chelators (HEDTA, EGTA) and low molecular weight organic acids (LMWOA) such as citric acid were compared on cadmium (Cd) solution in soils that were artificially contaminated. Also Cd phytoextraction capability by radish (Raphanus Sativus L.) was studied. The experiment was laid out in a randomized complete factorial design where each treatment was replicated three times. Concentration treatments of cadmium using CdCl2 were O(control), 5, 20, 60 and 100 mg Cd kg"1. After complete growth of plants, 6, 20 and 20 mMkg"1 soil HEDTA, EGTA and Citric Acid were added per pot, keeping a control without any chelator application. In order to determine cadmium concentration ten days after adding, chelates, samples were taken from the plants and soil of pots. The results showed that in all treatments the concentration of soluble Cd in soil was higher than the control. Also the results showed that synthetic chelators as compared with LMWOA (Citric Acid) have increased the solution remarkably. Among the other chelates, HEDTA had significant effects on Cd solution. In the current study, Cd concentration in shoot and root of {Raphanus Sativus L.) was increased with enhancement of Cd concentration in soil. Cd concentrations in shoots of radish were higher than those in roots. This could refer to higher bioavailability and solubility of Cd. In the current study, in all the treatments with HEDTA Cd concentrations in shoot and root of {Raphanus Sativus L.) were increased as compared with other chelates..