To select suitable plants for phytoextraction of Cd-contaminated soils, we evaluated the phytoextraction potential of five local Cd-accumulators: Amaranthus hypochondriacus L., Solanum nigrum L., Phytolacca acinosa Roxb., Celosia argentea L., and Sedum spectabile Boreau. The plants were grown in three naturally contaminated soils with different total Cd levels (1.57, 3.89, and 22.4 mg kg-1). Throughout the experimental period, no plants showed any visible symptoms of metal toxicity. The Cd uptake of C. argentea was the greatest in the S-YS soil (105 μg plant-1) and among the greatest in the S-HC soil and S-TJ soil. Besides, C. argentea exhibited the highest bioconcentration factor (12.3) in three soils. To improve the phytoextraction efficiency of C. argentea, we applied four low molecular weight organic acids (LMWOAs): tartaric acid, malic acid, oxalic acid, and citric acid. Malic acid was more effective in enhancing Cd uptake by C. argentea than the other LMWOAs. Therefore, C. argentea may be a potential choice in actual remediation projects. Moreover, application of malic acid is an effective way to increase the phytoextraction efficiency of C. argentea.

中文翻译：

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植物提取镉污染的土壤：植物种类和低分子量有机酸的比较。

为了选择合适的植物进行Cd污染土壤的植物提取，我们评估了5种本地Cd累积剂的植物提取潜力：A菜，蓝茄，茄子疫菌，鸡冠花（Celosia argentea L.）和景天景天（Sedum spectabile Boreau）。这些植物生长在三种自然污染的土壤中，镉的总含量不同（1.57、3.89和22.4 mg kg-1）。在整个实验期间，没有植物显示出任何明显的金属毒性症状。在S-YS土壤（105μgplant-1）中，银假丝酵母的Cd吸收最大，在S-HC土壤和S-TJ土壤中最大。此外，C。argentea在三种土壤中均表现出最高的生物浓缩系数（12.3）。为了提高弓形虫的植物提取效率，我们使用了四种低分子量有机酸（LMWOA）：酒石酸，苹果酸，草酸和柠檬酸。苹果酸比其他LMWOAs更有效地提高了C. argentea对Cd的吸收。因此，C。argentea可能是实际修复项目中的潜在选择。此外，苹果酸的应用是提高银杏茶的植物提取效率的有效途径。