Zhang Yuhan, Jia Jibao, Wei Shuhe, Zhan Jie, Kong Guannan, Wang Baoyu, Robinson Brett H, Skuza Lidia, Xue Jianming, Dai Huiping
School of Biological Science & Engineering, Shaanxi University of Technology, Hanzhong 723001, China.
Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, School of Ecology and Environmental Science, Yunnan University, Kunming 650500, China.
Sci Total Environ. 2025 Aug 10;989:179885. doi: 10.1016/j.scitotenv.2025.179885. Epub 2025 Jun 11.
Solanum nigrum L. has attracted scientific interest due to its capacity to accumulate exceptionally high cadmium (Cd) concentrations. Previous studies, which utilized different S. nigrum ecotypes reported varying levels of phytoremediation potentials for Cd pollution. However, due to differing experimental conditions, identifying the ecotype with the highest remediation potential has been challenging. The present article describes experiment involving nutrient solutions with two Cd concentrations [0.2 mg L Cd (T1), and 5 mg L Cd (T2)] to compare Cd accumulation differences in three S. nigrum ecotypes. The results showed that Cd accumulation was highest in the Suqian (SQ) ecotype, followed by Harbin (HRB) and Qingdao (QD) ecotypes. Cd concentrations in the roots, stems, leaves, and shoots of SQ were significantly increased by 31.0 %, 61.4 %, 29.1 %, and 43.1 %, respectively, in T1, and by 54.8 %, 57.6 %, 59.2 %, and 61.2 %, respectively, in T2 compared to QD. Correspondingly, Cd accumulation capacity (μg plant) in SQ shoots were also the highest, and increased significantly by 95.2 % compared to QD under T2 conditions, respectively, indicating its very high phytoremediation potential. Notably, the biomass of the SQ ecotype was also the highest in all treatments. Moreover, this ecotype demonstrated higher chlorophyll a and b, carotenoid contents, net photosynthetic rate, transpiration rate, stomatal conductance, SOD activity, and the lowest MDA content. These physiological characteristics may have contributed to the higher stress tolerance of the SQ ecotype. The present findings provide valuable insights for identifying and screening S. nigrum ecotypes with hyperaccumulate Cd accumulation potential worldwide.
龙葵因其能够积累极高浓度的镉（Cd）而引起了科学界的关注。以往的研究使用了不同的龙葵生态型，报告了其对Cd污染的不同植物修复潜力水平。然而，由于实验条件不同，确定具有最高修复潜力的生态型一直具有挑战性。本文描述了一项实验，该实验使用了两种Cd浓度的营养液[0.2 mg L Cd（T1）和5 mg L Cd（T2）]，以比较三种龙葵生态型在Cd积累方面的差异。结果表明，Cd积累量在宿迁（SQ）生态型中最高，其次是哈尔滨（HRB）和青岛（QD）生态型。与QD相比，在T1中，SQ的根、茎、叶和地上部的Cd浓度分别显著增加了31.0%、61.4%、29.1%和43.1%，在T2中分别增加了54.8%、57.6%、59.2%和61.2%。相应地，在T2条件下，SQ地上部的Cd积累能力（μg/株）也最高，与QD相比分别显著增加了95.2%，表明其具有很高的植物修复潜力。值得注意的是，在所有处理中，SQ生态型的生物量也是最高的。此外，该生态型表现出较高量的叶绿素a和b、类胡萝卜素含量、净光合速率、蒸腾速率、气孔导度、超氧化物歧化酶（SOD）活性，以及最低的丙二醛（MDA）含量。这些生理特征可能有助于SQ生态型具有更高的胁迫耐受性。本研究结果为在全球范围内鉴定和筛选具有超积累Cd潜力的龙葵生态型提供了有价值的见解。
