| 摘要: |
| 为探讨气孔导度对叶片水势的响应及其反馈调节机制，本研究以葡萄为试材，对不同节位叶片气孔导度和水势变化的规律及其相互关系进行了分析。结果显示，在浇水良好的条件下，不同节位叶片水势没有差异，但气孔导度却随着叶片节位升高而增大。部分根系在干旱的早期（停止浇水4 d内），也就是在叶片水势还没有明显下降时气孔导度即开始大幅度下降，意味着此时气孔导度的变化可能是由系统化学信号操纵的；在干旱的中期（停止浇水7 d左右），气孔导度和叶片水势随叶片节位变化呈明显的直线负相关。在整根干旱胁迫下，气孔导度随叶片水势的下降而急剧下降，两者呈现显著的指数关系。结果表明：葡萄不同节位叶片对干旱胁迫响应的敏感度不同，且在干旱的不同时期及不同条件下，叶片水势和系统化学信号对气孔运动起着协同调控的作用，这些结果对深入解析葡萄等藤本植物抗旱的生理机制提供了重要信息。 |
| 关键词: 葡萄 气孔导度 叶片水势 叶片节位 干旱 |
| DOI：10.11841/j.issn.1007-4333.2014.04.11 |
| 投稿时间：2014-01-17 |
| 基金项目:国家自然科学基金资助项目（31171921） |
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| Correlation analysis between leaf conductance and water potential changes during drought stress in grapevine |
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JI Wen-long, FAN Yi-juan, LI Chen, WEI Ling-zhi, JIANG Jin-zhu, LI Bing-bing, JIA Wen-suo
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| (College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China) |
| Abstract: |
| Regulation of leaf stomatal movement and water potential is one of the most important mechanisms for plant's resistance to drought stress.Using grapevine as research material,this study aims to understand the correlation between leaf conductance and leaf water potential among different node positions during the process of water stress.The results showed that,under the well watered condition,there was no difference in leaf water potential among different leaf node positions,but the leaf conductance increased along with the increase in the node height position.In the early stage under the partial root drying condition (PRD),leaf conductance declined significantly when no changes occurred in the leaf water potential,indicating that the changes of leaf conductance were a result of systemic chemical signaling;in the middle stage of PRD,leaf conductance showed a negative correlation with the leaf water potential among different node positions.Under the drought stress condition of whole roots,both leaf conductance and leaf water potential declined dramatically,and these two parameters showed a tight exponential correlation.Taken together,these results demonstrate that stomatal sensitivity to drought stress changes among the leaves located at different node positions,and under different stages and conditions,leaf conductance may be differently regulated by a synergistic function of hydraulic and chemically signaling.These observations are valuable for a deep understanding of the mechanisms behind drought resistance in grapevine. |
| Key words: grapevine stomatal conductance leaf water potential leaf node position drought |
