Effect of ethylene diamine tetra acetic acid chelator in the presence of chromium on growth and some physiological characteristics of sunflower.

Chromium is a heavy metal toxic for plants that due extensive industrial applications over the last decade, has become a serious environmental pollution. On the other hand, chelator dissolution and absorption of metal by the plant increase and their use in phytoremediation is important. The aim of this study was to evaluate the effect of different concentrations of chromium and ethylene diamine tetra acetic acid (EDTA) chelator on sunflower (Heliantus annuus L.) through the study of growth parameters, chlorophyll, and soluble sugar amounts and Cr accumulation in plants under hydroponic culture. In order to plant sunflower were treated with different concentrations of Cr (1, 2, 4 and 6 ppm) and EDTA (0, 1 and 3 mg/L) in the medium Hoagland. The results showed that the use of chromium reduced the length of shoots and roots, and chlorophyll, while it increased soluble sugars. Addition of EDTA to the metal increased the shoot and root length and chlorophyll content while it reduced soluble sugars. According to the results, the use of chromium heavy metal in medium increased the amount of it in shoot and root. EDTA application, particularly with higher levels of chromium led to its accumulation in shoot and root. This research suggested positive role of application of EDTA in the presence of chromium heavy metal in increasing the power of phytoremediation of sunflower.