Department of Horticulture, Purdue University, Lafayette, Indiana 47907.
Plant Physiol. 1972 May;49(5):842-7. doi: 10.1104/pp.49.5.842.
The closure of stomata by abscisic acid was examined in several species of plants through measurements of CO(2) and H(2)O exchange by the leaf. The onset of closure was very rapid, beginning at 3 minutes from the time of abscisic acid application to the cut base of the leaf of corn, or at 8 or 9 minutes for bean, Rumex and sugarbeet; rose leaves were relatively slow at 32 minutes. The timing and the concentration of abscisic acid needed to cause closure were related to the amounts of endogenous abscisic acid in the leaf. Closure was obtained in bean leaves with 8.9 picomoles/cm(2). (+)-Abscisic acid had approximately twice the activity of the racemic material. The methyl ester of abscisic acid was inactive, and trans-abscisic acid was likewise inactive. The effects of stress on levels of endogenous abscisic acid, and the ability of very small amounts of abscisic acid to cause rapid closure suggests that stomatal control is a regulatory function of this hormone.
通过测量叶片的 CO2 和 H2O 交换，研究了几种植物中叶中脱落酸引起的气孔关闭。气孔关闭发生得非常迅速，从玉米叶片切口底部涂抹脱落酸后 3 分钟开始，或在 8 或 9 分钟后在豆科植物、酸模属和糖甜菜中开始；玫瑰叶片则相对较慢，需 32 分钟。引起关闭所需的脱落酸的时间和浓度与叶片中内源性脱落酸的含量有关。在豆科植物叶片中，8.9 皮摩尔/平方厘米即可引起关闭。(+)-脱落酸的活性约为外消旋体的两倍。脱落酸的甲酯没有活性，反式脱落酸也没有活性。胁迫对内源脱落酸水平的影响，以及极少量脱落酸能迅速引起关闭的能力表明，气孔控制是这种激素的一种调节功能。
