| چکیده انگلیسی مقاله |
Background: Gradually increased concentration of heavy metals in soil is associated with serious hazards to human health and other living organisms. In this study, the optimal operating conditions in phytoremediation of soils contaminated with zinc heavy metal by Spinaciaoleracea L. plant were examined. Methods: In this experimental study, different concentrations of zinc chloride (0, 100, 250, 500, 1000, 1500, and 2000 μM) were applied to Spinaciaoleracea L. plant in the four-leaf stage in hydroponic culture medium for four weeks. Then, the growth and physiologic parameters, as well as the amount of the zinc element accumulated on their root and aerial organs were measured. The experiment was carried out with completely randomized design at three treatment levels. Findings: In the Spinaciaoleracea L. plant, with the increase in the zinc chloride content of the nutrient solutions, the biomass of the root and aerial part, chlorophyll a, total chlorophyll, and leaf area increased significantly, with the highest reduction related to the treatment of 2000 μM zinc chloride. The proline accumulation increased significantly in aerial part of the Spinaciaoleracea L. plant with the increase in zinc concentration, so that in 2000 μM zinc treatment, the accumulation rate was 2.57 times more than that of the control treatment. In Spinaciaoleracea L., the zinc accumulation rates in 2000 mM were 324.02 and 355.46 mg/kg of dry weight in aerial and root sections, respectively. Conclusion: Since the Spinaciaoleracea L. plant is resistant to low zinc concentrations in terms of indices of growth, chlorophyll a, total chlorophyll, carbohydrates, and leaf area, and as it has a relatively short growth priod as well as a high performance, it seems that this plant can be exploited in soils contaminated with zinc or lands affected by the wastes of industrial factories to refine them. |