Hajibagheri M A, Harvey D M R, Flowers T J
School of Biological Sciences, The University of Sussex, Brighton BN1 9QG, UK.
New Phytol. 1987 Mar;105(3):367-379. doi: 10.1111/j.1469-8137.1987.tb00874.x.
Significant varietal differences were apparent in the survival of seedlings of maize in saline conditions but only at relatively high external concentrations (200 mol m NaCl), where there was a range from 0 to 66% survival, 25 d after salinization. For the varieties examined there was a strong negative correlation between Na concentrations in the third leaf and survival. Two resistant varieties (Across 8024 and Protador) and one salt-sensitive variety (LG ) were identified. The characteristics of ion accumulation were clearly different in salt-tolerant and salt-sensitive types, the difference becoming more pronounced with plant age. The distribution of ions, particular those of Na, K and Cl, was determined within subcellular compartments of roots cells using X-ray microanalysis of freeze-substituted tissue. Salinity induced a greater increase (about 1.7 times) in cytoplasmic Na concentration in the salt-sensitive variety (LG ) than in resistant varieties (Across 8024 or Protador). The mean K:Na ratio in the cytoplasm of the root cortical cells in the salt-resistant varieties grown for 15 d in saline conditions (100 mol m NaCl) was twice that found for LG . Sodium and Cl concentrations in the vacuoles decreased radially inwards from the epidermal cells in salt-treated roots of LG .
在盐胁迫条件下，玉米幼苗的存活率存在显著的品种差异，但仅在相对较高的外部浓度（200 mol m NaCl）下才明显，盐处理25天后，存活率范围为0至66%。在所研究的品种中，第三片叶子中的钠浓度与存活率之间存在很强的负相关。鉴定出了两个抗性品种（Across 8024和Protador）和一个盐敏感品种（LG）。耐盐型和盐敏感型的离子积累特征明显不同，且随着植株年龄的增长，这种差异变得更加明显。使用冷冻替代组织的X射线微分析技术，确定了根细胞亚细胞区室中离子的分布，特别是钠、钾和氯的分布。盐胁迫导致盐敏感品种（LG）细胞质中钠浓度的增加幅度（约1.7倍）大于抗性品种（Across 8024或Protador）。在盐胁迫条件（100 mol m NaCl）下生长15天的抗盐品种根皮层细胞质中的平均钾钠比是LG品种的两倍。在LG品种经盐处理的根中，液泡中的钠和氯浓度从表皮细胞径向向内降低。
