Hu Miaohao H, Yuan Juhong H
Institute of Poyang Lake Eco-economics, Jiangxi University of Finance and Economics, Nanchang, 330032, Jiangxi, China,
Ecotoxicology. 2015 Apr;24(3):686-99. doi: 10.1007/s10646-014-1415-3. Epub 2015 Jan 8.
Chemically enhanced phytoremediation has been proposed as an effective approach to remove heavy metals from contaminated soil through the use of high biomass production plants. This study investigated changes in the spectral pattern of selenium (Se) accumulation in Coleus blumei Benth. (coleus) plants grown in hydroponics with 1.0 mg/l sodium selenite (Na2SeO3) and the effects of (S,S)-ethylenediamine disuccinic acid (EDDS) thereon through X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDXS) and Fourier transform infrared (FTIR) spectroscopy analyses. When EDDS concentrations were in the range of 0-1.0 mmol/l, Se content increased significantly; however, at EDDS concentrations above this range, the symptoms of Se toxicity were alleviated in coleus leaves. Application of EDDS over 1.0 mmol/l significantly decreased total Se uptake in the leaves and roots of the plants. The powder diffraction patterns of the roots and leaves displayed sharp crystalline peaks, which were characteristic of an organic molecule with crystallinity. Our results revealed the presence of high amounts of C, O, Mg, Al, Si, K and Ca in the roots and leaves under Se-induced stress with different concentrations of EDDS. There were no changes in the chemical compositions of the roots and leaves, but the contents were influenced by Se-induced stress and EDDS treatment. This study demonstrated the importance of applying XRD, EDXS and FTIR methods toward a more comprehensive understanding of the mechanisms of EDDS-induced Se accumulation in plants.
化学强化植物修复已被提议作为一种通过使用高生物量生产植物从污染土壤中去除重金属的有效方法。本研究通过X射线衍射（XRD）、能量色散X射线光谱（EDXS）和傅里叶变换红外（FTIR）光谱分析，研究了在含有1.0毫克/升亚硒酸钠（Na2SeO3）的水培条件下生长的彩叶草（Coleus blumei Benth.）植物中硒（Se）积累的光谱模式变化以及（S,S）-乙二胺二琥珀酸（EDDS）对其的影响。当EDDS浓度在0-1.0毫摩尔/升范围内时，硒含量显著增加；然而，当EDDS浓度高于此范围时，彩叶草叶片中硒毒性症状得到缓解。施用超过1.0毫摩尔/升的EDDS显著降低了植物叶片和根部的总硒吸收量。根和叶的粉末衍射图谱显示出尖锐的结晶峰，这是具有结晶性的有机分子的特征。我们的结果表明，在不同浓度EDDS的硒诱导胁迫下，根和叶中存在大量的碳、氧、镁、铝、硅、钾和钙。根和叶的化学成分没有变化，但含量受硒诱导胁迫和EDDS处理的影响。本研究证明了应用XRD、EDXS和FTIR方法对于更全面理解EDDS诱导植物中硒积累机制的重要性。
