School of Water Conservancy and Environment, University of Jinan, No. 336, West Road of Nan Xinzhuang, Jinan, 250022, Shandong Province, China.
Shandong Academy of Forestry, No. 42, East Road of Wenhua Road, Jinan, 250014, Shandong Province, China.
Environ Sci Pollut Res Int. 2019 Jul;26(19):19770-19784. doi: 10.1007/s11356-019-05331-7. Epub 2019 May 14.
Cd and Pb are a toxic environmental pollutant, and their elevated concentrations in the waters and soils could exert detriment effects on human health by food chain. In order to evaluate the capacity to heavy metal accumulation and the physiochemical responses of two Salix genotypes, a 35-day hydroponic seedling experiment was implemented with Salix matsudana Koidz. 'Shidi1' (A42) and Salix psammophila C. 'Huangpi1' (A94) under different concentrations of Cd (15 and 30 μM) or Pb (250 and 300 μM). The results showed that the biomass of A94 severely reduced more than that of A42. The accumulation ability of Cd in different plant organs followed the sequence of leaves > roots > stems. Pb primarily accumulated in the roots for both Salix genotypes (54.27 mg g for A42 and 54.52 mg g for A94). Translocation factors based on accumulation (TF') for Cd were more than 8.0, while TF's for Pb were less than 1.0 in both A42 and A94, implying they could be applied in the phytoremediation of Cd-contaminated sites due to their stronger ability to Cd phytoextraction. The stress of Cd or Pb significantly increased malondialdehyde (MDA) contents and increased photosynthetic rates in leaves of two Salix genotypes. Transpiration rates of willow were positively correlated with its Cd translocation. Both catalase (CAT) and peroxidase (POD) activities were suppressed, while the superoxide dismutase (SOD) was boosted with increasing Cd and Pb levels in the leaves and roots of the two willow genotypes, suggesting SOD plays an important role in the removal of ROS. The inconsistency of the changes in enzyme activity suggests that the integrated antioxidative mechanisms regulate the tolerance to Cd and Pb stress.
镉和铅是有毒的环境污染物，它们在水体和土壤中的浓度升高，可能通过食物链对人类健康产生不利影响。为了评估两种柳树基因型对重金属积累的能力和生理化学响应，进行了为期 35 天的水培幼苗实验，使用了柳树品种‘石堤 1 号’（A42）和‘黄皮 1 号’（A94），在不同浓度的镉（15 和 30 μM）或铅（250 和 300 μM）下。结果表明，A94 的生物量比 A42 严重减少。不同植物器官对 Cd 的积累能力依次为叶片＞根＞茎。Pb 主要在两种柳树基因型的根中积累（A42 为 54.27mg/g，A94 为 54.52mg/g）。基于积累的 Cd 迁移因子（TF'）大于 8.0，而 Pb 的 TF'小于 1.0，这表明它们可以应用于 Cd 污染场地的植物修复，因为它们具有更强的 Cd 植物提取能力。Cd 或 Pb 的胁迫显著增加了两种柳树基因型叶片中的丙二醛（MDA）含量和光合速率。柳树的蒸腾速率与 Cd 的迁移呈正相关。两种柳树基因型叶片和根中的 CAT 和 POD 活性受到抑制，而 SOD 活性随着 Cd 和 Pb 水平的升高而升高，这表明 SOD 在清除 ROS 中起重要作用。酶活性变化的不一致表明，综合抗氧化机制调节对 Cd 和 Pb 胁迫的耐受性。
