【摘要】 在T-80的作用下,与夜间气孔开放、蒸腾提高的同时,玉米叶片含水率及水势明显下降,水分饱和亏缺程度增大,此时,虽然气孔在黑暗中开放,但K~+并未在保卫细胞内累积,而且,脱落酸也不能阻止这种气孔的夜间开放及蒸腾的提高。在被水蒸汽饱和的环境中,T-80处理与对照一样,蒸腾停止进行,T-80亦不再能使玉米气孔在黑暗中开放,叶片水势下降及水分饱和亏缺度增大的现象均随之消失。 T-80引起玉米气孔在黑暗中开放这一现象,与一般情况下和K~+主动转移相关联的气孔主动开放运动不同,很可能是T-80改变了角质层的状况,使角质蒸腾大幅度提高,由此引起叶片含水率及水势的下降,进而引起表皮细胞膨压的下降,最终导致气孔的被动开放。更多还原

【Abstract】 When a maize leaf was put under the influence of Tween-80, it was foundthat, as the stomata remained open in darkness and transpiration was increased,there was a marked decrease in the water content and water potential as well as anobvious increase in water saturation deficit, with no K~+ accumulation in theguard cells. Abscisic acid did not prevent the occurrence of these phenomena. But when Tween treated leaves are left in a moisture-saturated environment, theinfluence of Tween-80 was offset. It is opined that the Tween-80 induced opening of the stomata in maizeleaves is different from the active opening which follows traslocation of K~+ and canbe prevented by the action of abscisic acid, in being a passive opening, possiblycaused by a decrease in turgor pressure in the epidermis due to the changes in themoisture conditions in the leaves, and these changes, in turn, resulting probablyfrom some change in the cuticle with an obvious increase in cuticular transpira-tion.更多还原