PDF(Pubmed)
Abstract：
High rates of fluorosis were reported worldwide as a result of human consumption of water with fluoride contents. Adjusting fluoride concentration in water as recommended by the World Health Organization (<1.5 mg L-1) is a concern and it needs to be conducted through inexpensive, but efficient techniques, such as phytoremediation. The application of phytohormones was investigated as a strategy to improve this process. Thus, the main goal of this research was to evaluate the effect of exogenous auxin and gibberellin on the tropical duckweed Eichhornia crassipes performance for fluoride phytoremediation. Definitive screening and central composite rotatable designs were used for experiments where fluoride concentration (5~15 mg L-1), phosphorus concentration (1~10 mg L-1), and pH (5~9) were assessed as well throughout 10 days. Fluoride contents were determined in solution and plant tissues by potentiometry. Higher concentrations of fluoride reflected on greater absorptions by plants, though in relative terms removal efficiencies were quite similar for all treatments (~60%). Auxin and acidic conditions favored fluoride removals per mass of plant. Fluoride accumulated mostly in leaves and auxin probably alleviated toxic effects on E. crassipes while gibberellin showed no effect. Therefore, E. crassipes could be employed as a fluoride accumulator plant for water treatment and exogenous auxin may be used to improve the process.
摘要：
据报道，由于人类食用含有氟化物的水，全世界的氟中毒发生率很高。根据世界卫生组织（<1.5mgL-1）的建议调整水中的氟化物浓度是一个问题，需要通过廉价的方式进行，但是有效的技术，如植物修复。研究了植物激素的应用作为改善该过程的策略。因此，本研究的主要目的是评估外源生长素和赤霉素对热带浮萍凤眼莲氟化物植物修复性能的影响。最终筛选和中心复合可旋转设计用于氟化物浓度（5〜15mgL-1）的实验，磷浓度（1~10mgL-1），和pH(5~9)也在整个10天进行评估。通过电位法测定溶液和植物组织中的氟化物含量。更高浓度的氟化物反映在植物的更大吸收上，尽管相对而言，所有处理的去除效率都非常相似(~60%)。生长素和酸性条件有利于每质量植物的氟化物去除。氟化物主要在叶片中积累，生长素可能减轻了对E.crassipes的毒性作用，而赤霉素则没有作用。因此,E.crassipes可以用作水处理的氟化物蓄积设备，并且可以使用外源生长素来改善该过程。
