Northeast Forestry University, Harbin 150040, Heilongjiang, People's Republic of China.
Can J Microbiol. 2013 Jul;59(7):449-55. doi: 10.1139/cjm-2012-0650. Epub 2013 May 13.
Phytoremediation combined with suitable microorganisms and biodegradable chelating agents can be a means of reclaiming lands contaminated by toxic heavy metals. We investigated the ability of a lead- and cadmium-resistant bacterial strain (JB12) and the biodegradable chelator ethylenediamine-N,N'-disuccinic acid (EDDS) to improve absorption of these metals from soil by tall fescue and red clover. Strain JB12 was isolated from contaminated soil samples, analysed for lead and cadmium resistance, and identified as Burkholderia cepacia. Tall fescue and red clover were grown in pots to which we added JB12, (S,S)-EDDS, combined JB12 and EDDS, or water only. Compared with untreated plants, the biomass of plants treated with JB12 was significantly increased. Concentrations of lead and cadmium in JB12-treated plants increased significantly, with few exceptions. Plants treated with EDDS responded variably, but in those treated with combined EDDS and JB12, heavy metal concentrations increased significantly in tall fescue and in the aboveground parts of red clover. We conclude that JB12 is resistant to lead and cadmium. Its application to the soil improved the net uptake of these heavy metals by experimental plants. The potential for viable phytoremediation of lead- and cadmium-polluted soils with tall fescue and red clover combined with JB12 was further enhanced by the addition of EDDS.
植物修复与合适的微生物和可生物降解的螯合剂相结合，可以成为回收受有毒重金属污染土地的一种手段。我们研究了耐铅和镉的细菌菌株 (JB12) 和可生物降解的螯合剂乙二胺二琥珀酸 (EDDS) 提高羊茅和红三叶草从土壤中吸收这些金属的能力。菌株 JB12 从污染土壤样本中分离出来，对其耐铅和镉能力进行了分析，并鉴定为伯克霍尔德氏菌。羊茅和红三叶草在盆中生长，我们向其中添加了 JB12、(S,S)-EDDS、JB12 和 EDDS 的混合物或仅加水。与未处理的植物相比，用 JB12 处理的植物的生物量显著增加。除了少数例外，用 JB12 处理的植物中铅和镉的浓度显著增加。用 EDDS 处理的植物反应不一，但在 EDDS 和 JB12 联合处理的植物中，羊茅和红三叶草地上部分的重金属浓度显著增加。我们得出结论，JB12 耐受铅和镉。将其应用于土壤可提高实验植物对这些重金属的净吸收。通过添加 EDDS，用羊茅和红三叶草与 JB12 结合进行可行的植物修复受铅和镉污染土壤的潜力进一步增强。
