School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, People's Republic of China.
Environ Sci Pollut Res Int. 2022 Jun;29(26):39017-39026. doi: 10.1007/s11356-022-19562-8. Epub 2022 Mar 19.
Macleaya cordata (Willd.) R. Br. are proposed for the application in phytoremediation of heavy metal-contaminated soil. In this paper, the physiological response, subcellular distribution, chemical form, ultrastructure, and manganese (Mn) absorption characteristics of M. cordata under the stress of 0, 3, 6, 9, 12, and 15 mmol/L manganese concentration were studied by sand culture experiment. The results showed that M. cordata seedlings show high tolerance to Mn stress with a concentration of less than 6 mmol/L, while higher Mn concentration showed a significant toxic effect. A low concentration of Mn (≤ 6 mmol/L) can promote the synthesis of chlorophyll and soluble protein; furthermore, superoxide dismutase and peroxidase activities responded positively. The accumulation of Mn in the inactive metabolic part (cell wall and vacuole) of M. cordata leaves might be one of the main Mn detoxification mechanism. According to the ultrastructure of M. cordata, high-concentration Mn (≥ 12 mmol/L) stress can cause M. cordata cells to be distorted and deformed, black precipitates appeared in the intercellular space, mitochondria decrease, chloroplasts shrink, hungry particles increased, and starch granules decrease. The uptake ability of different tissues for Mn is leaf > root > stem, and transport coefficient decreases with the increase of Mn concentration. Clearly, M. cordata has a certain tolerance to manganese, which has the ecological application potential in Mn-polluted areas.
三叶崖爬藤（Macleaya cordata (Willd.) R. Br.）被提议应用于重金属污染土壤的植物修复。本文通过砂培实验，研究了 0、3、6、9、12 和 15 mmol/L 锰浓度胁迫下三叶崖爬藤的生理响应、亚细胞分布、化学形态、超微结构和锰（Mn）吸收特性。结果表明，三叶崖爬藤幼苗对 Mn 胁迫具有较高的耐受性，浓度低于 6 mmol/L 时，而较高的 Mn 浓度表现出明显的毒性作用。低浓度 Mn（≤6 mmol/L）能促进叶绿素和可溶性蛋白的合成，进一步提高超氧化物歧化酶和过氧化物酶的活性。Mn 在三叶崖爬藤叶片非活性代谢部位（细胞壁和液泡）中的积累可能是其主要的 Mn 解毒机制之一。根据三叶崖爬藤的超微结构，高浓度 Mn（≥12 mmol/L）胁迫会导致细胞变形，细胞间隙出现黑色沉淀，线粒体减少，叶绿体收缩，饥饿颗粒增加，淀粉粒减少。不同组织对 Mn 的吸收能力为叶＞根＞茎，且转运系数随 Mn 浓度的增加而降低。显然，三叶崖爬藤对锰具有一定的耐受性，在 Mn 污染地区具有生态应用潜力。
