| 摘要: |
| 有毒金属离子在植物组织中的分布和亚细胞水平的定位与植物对金属离子的耐受性密切相关。为探究铝进入马尾松体内后在亚细胞水平下的分布情况,该研究分别设置4个铝浓度0、0.5、1.0、2.0 mmol·L-1,通过盆栽试验研究不同铝浓度下马尾松的生长状况及亚细胞水平下铝的分配特征。结果表明:(1)低浓度铝(0.5 mmol·L-1)显著促进马尾松的生长(P<0.05),随铝浓度的升高(≥1.0 mmol·L-1),马尾松根系生长和根尖细胞活力均受到抑制。(2)相较于茎叶,进入马尾松体内的铝主要沉积在根系中(P<0.05),但随着铝浓度的增加,茎叶中的铝含量也开始增加。(3)亚细胞水平下,不同铝浓度影响了铝在细胞壁和液泡中的分配比例。当铝浓度为1.0 mmol·L-1及以下时,铝在根系和茎叶的细胞壁和液泡中的比例均较高,两者间铝含量差异不显著; 而高铝浓度下(2.0 mmol·L-1),铝则主要沉积在细胞壁上,根系、茎叶的细胞壁铝含量分别占比55%和70%。相较而言,各铝浓度处理下细胞器和细胞质中的铝含量均维持在较低水平,这降低了铝对细胞功能的影响。综上认为,马尾松可以通过调整体内铝的分配来适应铝胁迫,这为后续从细胞及分子层面进一步阐明马尾松对铝环境的适应机制奠定了理论基础。 |
| 关键词: 马尾松, 铝, 亚细胞组分, 细胞壁, 分配特征 |
| DOI：10.11931/guihaia.gxzw202305073 |
| 分类号:Q945 |
| 文章编号:1000-3142(2024)03-0521-10 |
| Fund project:国家自然科学基金(31971572,31500090); 贵州省科学技术基金(黔科合基础-ZK[2022]一般101); 贵州大学培育项目([2020]47)。 |
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| desertification area of Western Hunan |
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REN Heqin1,2, SUN Xueguang1,2*, YUAN Guiyun1,2, FENG Wanyan1,2
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1. Institute for Forest Resources and Environment of Guizhou/Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province,
Guizhou University, Guiyang 550025, China;2. College of Forestry, Guizhou University, Guiyang 550025, China
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| Abstract: |
| The distribution and subcellular localization of toxic metal ions in plant tissues are of great significance for plants to cope with metal stresses, which could provide valuable insights into the mechanisms underlying plant metal tolerance. To explore the distribution of aluminum(Al)at the subcellular level after entering Pinus massoniana, four aluminum concentrations of 0, 0.5, 1.0, 2.0 mmol·L-1 were set up in this study. The growth status of P. massoniana and the distribution characteristics of aluminum at the subcellular level under different Al concentrations were studied by pot experiment. The results were as follows:(1)P. massoniana exhibited significant growth enhancement under 0.5 mmol·L-1 Al treatment, and the biomass, seedling height, root length, as well as the number of lateral roots were all significantly promoted. However, higher Al concentrations(≥1 mmol·L-1)led to diminished growth promotion effects and inhibited root growth and cell viability in P. massoniana root tips.(2)Translocation of Al from roots to shoots in P. massoniana was limited. The absorbed Al was mainly deposited in the roots(P<0.05), although the accumulation of Al in the shoots increased along with the Al concentration increased.(3)At the subcellular level, different Al concentrations affected the proportions of absorbed Al deposited in cell walls and vacuoles. Under both 0.5 and 1.0 mmol·L-1Al treatments, the proportions of Al in both the cell walls and vacuoles of roots or shoots were all at higher levels compared with other cell components, and there was no significant difference between the Al contents of cell walls and vacuoles. However, at high Al concentration(2.0 mmol·L-1), a majority of deposited Al was found on the cell walls, accounting for 55% and 70% in root and shoot cells, respectively. In contrast, the Al contents in the organelles and cytoplasm maintained low levels of Al concentration treatments, which mitigated the adverse effects of Al on cellular functions. In summary, the presented results suggest that P. massoniana effectively adapted to Al stress through coordinated distribution and subcellular localization mechanisms for absorbed Al. This evokes the needs of further investigation of the adaptation mechanisms of P. massoniana to Al stress from both the cellular and molecular levels. |
| Key words: Pinus massoniana, aluminum(Al), subcellular components, cell wall, distribution characteristics |
