Sinhal V K, Srivastava Alok, Singh V P
Department of Plant Science, Faculty of Applied Sciences, M.J.P. Rohilkhand University, Bareilly 243 006, India.
J Environ Biol. 2010 May;31(3):255-9.
Phytoextraction is an emerging cost-effective solution for remediation of contaminated soils which involves the removal of toxins, especially heavy metals and metalloids, by the roots of the plants with subsequent transport to aerial plant organs. The aim of the present investigation is to study the effects of EDTA and citric acid on accumulation potential of marigold (Tagetes erecta) to Zn, Cu, Pb, and Cd and also to evaluate the impacts of these chelators (EDTA and citric acid) in combination with all the four heavy metals on the growth of marigold. The plants were grown in pots and treated with Zn (7.3 mg l(-1)), Cu (7.5 mg I(-1)), Pb (3.7 mg l(-1)) and Cd (0.2 mg l(-1)) alone and in combination with different doses of EDTA i.e., 10, 20 and 30 mg l(-1). All the three doses of EDTA i.e., 10, 20 and 30 mg l(-1) significantly increased the accumulation of Zn, Cu, Pb and Cd by roots, stems and leaves as compared to control treatments. The 30 mg l(-1) concentration of citric acid showed reduced accumulation of these metals by root, stem and leaves as compared to lower doses i.e., 10 and 20 mg l(-1). Among the four heavy metals, Zn accumulated in the great amount (526.34 mg kg(-1) DW) followed by Cu (443.14 mg kg(-1) DW), Pb (393.16 mg kg(-1) DW) and Cd (333.62 mg kg(-1) DW) in leaves with 30 mg l(-1) EDTA treatment. The highest concentration of EDTA and citric acid (30 mg l(-1)) caused significant reduction in growth of marigold in terms of plant height, fresh weight of plant, total chlorophyll, carbohydrate content and protein content. Thus EDTA and citric acid efficiently increased the phytoextractability of marigold which can be used to remediate the soil contaminated with these metals.
植物提取是一种新兴的、具有成本效益的污染土壤修复解决方案，它涉及植物根系去除毒素，特别是重金属和类金属，随后将其转运到地上植物器官。本研究的目的是研究乙二胺四乙酸（EDTA）和柠檬酸对万寿菊（孔雀草）积累锌、铜、铅和镉潜力的影响，并评估这些螯合剂（EDTA和柠檬酸）与所有四种重金属组合对万寿菊生长的影响。将植物种植在花盆中，分别单独用锌（7.3毫克/升）、铜（7.5毫克/升）、铅（3.7毫克/升）和镉（0.2毫克/升）处理，以及与不同剂量的EDTA（即10、20和30毫克/升）组合处理。与对照处理相比，所有三种剂量的EDTA（即10、20和30毫克/升）均显著增加了根、茎和叶对锌、铜、铅和镉的积累。与较低剂量（即10和20毫克/升）相比，30毫克/升浓度的柠檬酸显示根、茎和叶对这些金属的积累减少。在四种重金属中，用30毫克/升EDTA处理时，叶片中锌的积累量最大（526.34毫克/千克干重），其次是铜（443.14毫克/千克干重）、铅（393.16毫克/千克干重）和镉（333.62毫克/千克干重）。最高浓度的EDTA和柠檬酸（30毫克/升）在株高、植株鲜重、总叶绿素、碳水化合物含量和蛋白质含量方面导致万寿菊生长显著降低。因此，EDTA和柠檬酸有效地提高了万寿菊的植物提取能力，可用于修复被这些金属污染的土壤。
