中文摘要：

【目的】研究干旱条件下葡萄叶片气孔导度和水势随叶片节位变化的规律及其机理。【方法】利用3005F01植物水势测定仪和SC-1气孔计测量不同干旱程度下葡萄主梢各节位叶片气孔导度和水势。【结果】浇水良好的条件下,葡萄叶片气孔导度随叶片节位的升高而升高,且两者有很好的线性关系;轻度干旱可导致上部节位叶片气孔导度大幅度下降,而下部节位叶片气孔导度变化不大,叶片水势随着节位上升而提高;和轻度干旱相反,严重干旱时,叶片气孔导度随叶片节位的升高而下降,叶片水势仍然随着叶片节位的升高而上升,两者呈现出明显的线性关系。【结论】浇水良好的条件下,叶片气孔导度和叶片水势没有相关性;不同节位叶片对干旱的响应敏感度存在明显的差异,这种差异和叶片水势的变化及其反馈调节有密切的联系。

英文摘要：

【Objective】An experiment was conducted to study the regulations of the changes of stomatal conductance and water potential at different leaf positions under drought conditions.【Method】The stomatal conductance and water potential at different grape leaf positions were detected by 3005F01 Plant Water Status Console and SC-1 Leaf Porometer after drought treatments.【Result】Under well-watered condition,stomatal conductance had a positive linear correlation with the leaf position;However,a slight drought could reduce the stomatal conductance at upper leaf position significantly,with not much influence on lower leaf position.A contrast phenomenon was found under severe drought condition,the stomatal conductance declined with the increase in leaf position,while the water potential still had a positive correlation with leaf position.【Conclusion】No relationship between stomatal conductance and water potential under well-watered condition was found.The sensitivity to drought of leaves at different leaf positions had an obvious difference,which was closely related to the change of water potential and corresponding feedback regulation.