STOMATAL RESPONSE TO HUMIDITY IN SUGARCANE AND SOYBEAN - EFFECT OF VAPOR-PRESSURE DIFFERENCE ON THE KINETICS OF THE BLUE-LIGHT RESPONSE
STOMATAL RESPONSE TO HUMIDITY IN SUGARCANE AND SOYBEAN - EFFECT OF VAPOR-PRESSURE DIFFERENCE ON THE KINETICS OF THE BLUE-LIGHT RESPONSE
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DOI：
10.1111/j.1365-3040.1990.tb01288.x
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发表时间：
1990-03-01
影响因子：
7.3
通讯作者：
GRANTZ, DA
中科院分区：
文献类型：
--
作者：
ASSMANN, SM;GRANTZ, DA
在甘蔗(Saccharum spp.)气体交换实验中，定量研究了大气湿度对气孔响应动力学的影响。杂交种)和大豆(Glyine Max)。蓝光脉冲被用来诱导由保卫细胞的特定蓝光反应介导的气孔导度脉冲。电导响应的动力学参数与叶片-空气蒸气压差(VPD)的关系比与相对湿度或蒸腾作用的关系更密切。提高VPD显著加速了甘蔗和大豆的气孔开放，尽管甘蔗的气孔开放速度大约是甘蔗的五倍。相反，两种植物在脉冲后气孔恢复(关闭)的动力学是相似的。即使在大豆表现出蒸腾作用(E)随蒸腾需要量(VPD)增加的前馈反应的情况下，也观察到高VPD加速了开花。这一结果表明，表皮而不是整体叶片的水分状况对气孔动力学的VPD效应起到了中介作用。这些数据与这样的假设是一致的，即在高VPD时增加表皮水分损失会减少相邻细胞对保卫细胞施加的背压，从而允许单位保卫细胞对蓝光的代谢反应更快地打开气孔。
The effect of atmospheric humidity on the kinetics of stomatal responses was quantified in gas exchange experiments using sugarcane (Saccharum spp. hybrid) and soybean (Glycine max). Pulses of blue light were used to elicit pulses of stomatal conductance that were mediated by the specific blue light response of guard cells. Kinetic parameters of the conductance response were more closely related to leaf-air vapour pressure difference (VPD) than to relative humidity or transpiration. Increasing VPD significantly accelerated stomatal opening in both sugarcane and soybean, despite an approximately five-fold faster response in sugarcane. In contrast, the kinetics of stomatal recovery (closure) following the pulse were similar in the two species. Acceleration of opening by high VPD was observed even under conditions where soybean exhibited a feedforward response of decreasing transpiration (E) with increasing evaporative demand (VPD). This result suggests that epidermal, rather than bulk leaf, water status mediates the VPD effect on stomatal kinetics. The data are consistent with the hypothesis that increased epidermal water loss at high VPD decreases the backpressure exerted by neighbouring cells on guard cells, allowing more rapid stomatal opening per unit of guard cell metabolic response to blue light.