Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining, Anhui University of Science and Technology, Huainan, 232001, P. R. China.
Key Laboratory of Industrial Dust Prevention and Control & Occupational Safety and Health of the Ministry of Education, Anhui University of Science and Technology, Huainan, 232001, P. R. China.
PLoS One. 2024 May 15;19(5):e0302940. doi: 10.1371/journal.pone.0302940. eCollection 2024.
Miscanthus lutarioriparia is a promising energy crop that is used for abandoned mine soil phytoremediation because of its high biomass yield and strong tolerance to heavy metals. However, the biological mechanism of heavy metal resistance is limited, especially for applications in the soil restoration of mining areas. Here, through the investigation of soil cadmium(Cd) in different mining areas and soil potted under Cd stress, the adsorption capacity of Miscanthus lutarioriparia was analyzed. The physiological and transcriptional effects of Cd stress on M. lutarioriparia leaves and roots under hydroponic conditions were analyzed. The results showed that M. lutarioriparia could reduce the Cd content in mining soil by 29.82%. Moreover, different Cd varieties have different Cd adsorption capacities in soils with higher Cd concentration. The highest cadmium concentrations in the aboveground and belowground parts of the plants were 185.65 mg/kg and 186.8 mg/kg, respectively. The total chlorophyll content, superoxide dismutase and catalase activities all showed a trend of increasing first and then decreasing. In total, 24,372 differentially expressed genes were obtained, including 7735 unique to leaves, 7725 unique to roots, and 8912 unique to leaves and roots, which showed differences in gene expression between leaves and roots. These genes were predominantly involved in plant hormone signal transduction, glutathione metabolism, flavonoid biosynthesis, ABC transporters, photosynthesis and the metal ion transport pathway. In addition, the number of upregulated genes was greater than the number of downregulated genes at different stress intervals, which indicated that M. lutarioriparia adapted to Cd stress mainly through positive regulation. These results lay a solid foundation for breeding excellent Cd resistant M. lutarioriparia and other plants. The results also have an important theoretical significance for further understanding the detoxification mechanism of Cd stress and the remediation of heavy metal pollution in mining soil.
柳枝稷是一种很有前途的能源作物，由于其生物量大、耐重金属能力强，常被用于废弃矿山土壤的植物修复。然而，其重金属抗性的生物学机制尚不清楚，特别是在矿区土壤修复方面的应用。本研究通过调查不同矿区土壤和镉胁迫下的盆栽土壤，分析柳枝稷对镉的吸附能力，并在水培条件下分析镉胁迫对柳枝稷叶片和根系的生理和转录效应。结果表明，柳枝稷可以降低矿区土壤中 29.82%的镉含量。此外，不同镉形态在高镉浓度土壤中对镉的吸附能力也不同。植株地上部和地下部镉含量的最大值分别为 185.65mg/kg 和 186.8mg/kg。总叶绿素含量、超氧化物歧化酶和过氧化氢酶活性均表现为先升高后降低的趋势。共获得 24372 个差异表达基因，其中叶片特有基因 7735 个，根特有基因 7725 个，叶片和根共有的基因 8912 个，叶片和根的基因表达存在差异。这些基因主要参与植物激素信号转导、谷胱甘肽代谢、类黄酮生物合成、ABC 转运蛋白、光合作用和金属离子转运途径。此外，不同胁迫时间点上调基因的数量多于下调基因的数量，这表明柳枝稷主要通过正调控来适应镉胁迫。这些结果为培育优良的镉抗性柳枝稷和其他植物奠定了基础。本研究结果对进一步了解镉胁迫解毒机制和矿区重金属污染修复也具有重要的理论意义。
