Arnetoli Miluscia, Vooijs Riet, Gonnelli Cristina, Gabbrielli Roberto, Verkleij Jos A C, Schat Henk
Section of Plant Ecology and Physiology, Department of Plant Biology, University of Florence, via Micheli 1, 50121 Florence, Italy.
Environ Pollut. 2008 Nov;156(2):380-6. doi: 10.1016/j.envpol.2008.01.044. Epub 2008 Mar 14.
Cadmium and zinc tolerance were examined in populations of Silene paradoxa, one from uncontaminated calcareous soil (CVD) and one from a mine tailing (FC) (Cd<1-15 ppm, Zn 400-1300 ppm, pH 2-6). The mine population exhibited extremely high Zn and Cd tolerance levels, although the degrees of Cd and Zn enrichment relatively low at the population site. Cd and Zn hypertolerance in FC were associated with reduced rates of accumulation of these metals, both in roots and shoots (Cd), or exclusively in shoots (Zn). However, exclusion potentially explained only a minor part of the superior tolerance in FC. Cd hypertolerance in FC was associated with decreased, rather than enhanced phytochelatin accumulation. The remarkably high levels of Cd and Zn hypertolerance in FC might relate to the low soil pH, due to oxidation of sulphide minerals, and the absence of soil organic matter at the FC site.
在两种蝇子草种群中检测了镉和锌耐受性，一种来自未受污染的石灰质土壤（CVD），另一种来自矿渣（FC）（镉含量为1 - 15 ppm，锌含量为400 - 1300 ppm，pH值为2 - 6）。尽管在该种群所在地镉和锌的富集程度相对较低，但矿渣种群表现出极高的锌和镉耐受性水平。FC种群中对镉和锌的超耐受性与这些金属在根和地上部分（镉）或仅在地上部分（锌）的积累速率降低有关。然而，排斥作用可能仅解释了FC种群中超耐受性的一小部分。FC种群中对镉的超耐受性与植物螯合素积累的减少而非增加有关。FC种群中镉和锌的超耐受性水平极高可能与硫化物矿物氧化导致的低土壤pH值以及FC场地缺乏土壤有机质有关。
