University of Tehran Press Iranian Journal of Soil and Water Research 2008-479X 50 4 2019 08 23 Effect of Citric Acid, Nitrilotriacetic acid and Anion Polyacrylamide on Phytoremediation of Nickel by Maize and Sunflower Effect of Citric Acid, Nitrilotriacetic acid and Anion Polyacrylamide on Phytoremediation of Nickel by Maize and Sunflower 933 921 72503 10.22059/ijswr.2018.254627.667878 FA Elham Mohebbi Najmabadi MSc. Student, Department of Soil Science, Faculty of Agriculture, Ferdowsi University, Mashhad, Iran Amir Fotovat Professor, Department of Soil Science, Faculty of Agriculture, Ferdowsi University, Mashhad, Iran 0000-0002-5551-7002 Akram Halajnia Assistant Professor, Department of Soil Science, Faculty of Agriculture, Ferdowsi University, Mashhad, Iran Journal Article 2018 04 08 Soil contamination is one of the most important problems of modern societies. One of the serious pollutants in this area is nickel. Phytoremediation is one of the proposed methods that allow pollutants to be removed from the contaminated soils with pollutant accumulation in plants. In the case of heavy metal contamination, the use of soil chelating agents can increase the efficiency of this method. The aim of this study was to investigate the uptake of nickel from soil by maize (<em>Zea maize</em>) and sunflower (<em>Helianthus annuus</em>) in the presence of two levels of citric acid (5 and 10 mmol kg^-1 soil), two levels of nitrilotriacetic acid (NTA) (2.5 and 5 mmol kg^-1 soil) and two levels of anion polyacrylamide (APAM) (0.07 and 0.14 g kg^-1 soil). Control treatment was performed without chelate. This experiment was conducted as a completely randomized design with three replications in soils contaminated with nickel (200 mg Ni kg^-1 soil, added as Ni (NO₃)₂) under greenhouse conditions. The results showed that the most effective chelate in increasing the yield of maize (plant height, fresh and dry weight of shoot and root) was NTA chelate at its highest concentration. The highest increase of sunflower yield was obtained by applying CA chelate. NTA at high concentrations had the greatest effect on nickel available, nickel accumulation of shoot and total absorption in both plants compared to CA and APAM treatments. Based on the results, the use of maize and application of NTA at highest concentrations resulted a higher accumulation of nickel and increased transfer and refinement factors in the proposed plants. Soil contamination is one of the most important problems of modern societies. One of the serious pollutants in this area is nickel. Phytoremediation is one of the proposed methods that allow pollutants to be removed from the contaminated soils with pollutant accumulation in plants. In the case of heavy metal contamination, the use of soil chelating agents can increase the efficiency of this method. The aim of this study was to investigate the uptake of nickel from soil by maize (<em>Zea maize</em>) and sunflower (<em>Helianthus annuus</em>) in the presence of two levels of citric acid (5 and 10 mmol kg^-1 soil), two levels of nitrilotriacetic acid (NTA) (2.5 and 5 mmol kg^-1 soil) and two levels of anion polyacrylamide (APAM) (0.07 and 0.14 g kg^-1 soil). Control treatment was performed without chelate. This experiment was conducted as a completely randomized design with three replications in soils contaminated with nickel (200 mg Ni kg^-1 soil, added as Ni (NO₃)₂) under greenhouse conditions. The results showed that the most effective chelate in increasing the yield of maize (plant height, fresh and dry weight of shoot and root) was NTA chelate at its highest concentration. The highest increase of sunflower yield was obtained by applying CA chelate. NTA at high concentrations had the greatest effect on nickel available, nickel accumulation of shoot and total absorption in both plants compared to CA and APAM treatments. Based on the results, the use of maize and application of NTA at highest concentrations resulted a higher accumulation of nickel and increased transfer and refinement factors in the proposed plants. https://ijswr.ut.ac.ir/article_72503_7dadcec96773d2754b2750f1e8635227.pdf