摘要
正常水分状态下 ,玉米茎部木质部汁液 pH高于根部 ,ABA浓度高于根部和叶片 ;干旱胁迫条件下 ,根、茎木质部汁液 pH和ABA都有不同程度升高 ,叶片ABA含量最高。用2 0 0 μmol/L外源ABA处理 ,程度不同地提高根、茎和叶片木质部汁液ABA含量 ,但不能改变器官之间ABA的分布规律 ,却能诱导气孔关闭。不同浓度外源 pH溶液处理植株 ,木质部汁液 pH、蒸腾速率和气孔导度、木质部汁液ABA浓度变化表现出高度一致性。联系他人的研究结果推测 :干旱胁迫后 pH升高很可能通过改变组织和器官之间ABA含量比例 ,使叶片ABA达到足够浓度 ,从而调节气孔关闭 ,调控蒸腾速率。
Early signals potentially regulating evaporation and stomatal aperture in maize subjected to drought were investigated.Plants were grown in pot on loam.In normal water condition,xylem sap pH were higher in stem than that in roots.ABA concentrations in stems were higher than that of roots and leaves.When subjected to drought stress,pH and ABA concentration in xylem sap of both roots?stems and leaves increased,and ABA concentrations were highest in leaves.200 μmol/L exogenous ABA could increase xylem sap ABA concentration of roots,stems and leaves,but couldn't change ABA distribution in different tissue,while could induce stomata to close.Exogenous pH solution on xylem sap pH,ABA and evaporation and stomatal aperture indicated that pH could regulate stomatal aperture through accumulating ABA concentration in leaves.
出处
《河北农业科学》
2004年第2期35-39,共5页
Journal of Hebei Agricultural Sciences
基金
河北省自然科学基金资助项目 ( 3 0 2 466)
河北省农林科学院重点资助项目 (A0 3 1 0 2 14 )
