Zhi Yang, Zhou Qixing, Leng Xue, Zhao Chunlei
School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang, China.
Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education)/Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin, China.
Front Chem. 2020 Apr 8;8:222. doi: 10.3389/fchem.2020.00222. eCollection 2020.
In the process of remediation of contaminated soil, we should give full play to the role of low-energy plants and fully display the concept of modern energy-saving and environmental protection. Phytoremediation is an effective method to remediate cadmium-contaminated soil, and root exudates play an important part in this process. Here, the response of snapdragon in a pot-culture experiment under two concentrations of Cd (1.0 and 2.5 mg/kg) was evaluated. Snapdragon is a medicinal plant with low energy consumption, which has low requirements on environmental factors and strong resistance. The results showed that both Cd concentrations interfere with the uptake of B, P, Cu, Mn, Mo, and Zn by the soil. The results also showed that plant type and Cd stress can significantly change the concentrations and species of root exudates. The metabolic changes of root exudates revealed the active defense mechanism of plants to Cd stress: up-regulating of amino acids to sequester/exclude Cd, regulation of citric acid on chelation/complexation, and precipitation of cadmium ions. The application of snapdragon can effectively reduce energy consumption and gradually improve the utilization rate of vegetation, which promotes the degradation of cadmium pollutants in soil.
在污染土壤修复过程中，应充分发挥低能耗植物的作用，充分展现现代节能环保理念。植物修复是修复镉污染土壤的有效方法，根系分泌物在这一过程中发挥着重要作用。在此，评估了金鱼草在盆栽实验中对两种镉浓度（1.0和2.5毫克/千克）的响应。金鱼草是一种低能耗的药用植物，对环境因子要求低且抗性强。结果表明，两种镉浓度均会干扰土壤对硼、磷、铜、锰、钼和锌的吸收。结果还表明，植物类型和镉胁迫可显著改变根系分泌物的浓度和种类。根系分泌物的代谢变化揭示了植物对镉胁迫的主动防御机制：上调氨基酸以螯合/排除镉、柠檬酸对螯合/络合的调节以及镉离子的沉淀。金鱼草的应用可有效降低能耗并逐步提高植被利用率，从而促进土壤中镉污染物的降解。
