McAinsh Martin R, Evans Nicky H, Montgomery Lucy T, North Kathryn A
Institute of Environmental and Natural Sciences, Department of Biological Sciences, Lancaster University, Lancaster LA1 4YQ, UK.
New Phytol. 2002 Mar;153(3):441-447. doi: 10.1046/j.0028-646X.2001.00336.x. Epub 2002 Mar 5.
Stomatal responses to air pollutants are complex, varying among species and with concentration, environmental conditions and age. In general, short-term exposure to sulphur dioxide (SO ) promotes stomatal opening, whereas longer-term exposure can cause partial stomatal closure. By contrast, the effects of oxides of nitrogen (NO ) are often small or insignificant. The effects of ozone, and oxidative stress, are equally complex. Short-term exposure to ozone stimulates a rapid reduction in stomatal aperture, whilst longer-term exposure causes stomatal responses to become sluggish. The response of stomata to abscisic acid (ABA) has been shown to be slower in plants exposed to a combination of SO and NO suggesting an adverse effect on guard cell ABA signal transduction. In addition, ozone causes a reduction in stomatal closure under drought conditions. There is an increasing body of evidence to suggest that air pollutants and oxidative stresses can have a marked effect on the Ca homeostasis of guard cells and the intracellular machinery responsible for stomatal movements. Here we discuss the effects of air pollutants on stomatal responses and their possible effects on Ca based signalling in guard cells focusing on the effects of ozone and oxidative stress.
气孔对空气污染物的反应很复杂，因物种、污染物浓度、环境条件和植物年龄而异。一般来说，短期接触二氧化硫（SO₂）会促进气孔开放，而长期接触则会导致气孔部分关闭。相比之下，氮氧化物（NOₓ）的影响通常较小或不显著。臭氧和氧化应激的影响同样复杂。短期接触臭氧会促使气孔孔径迅速减小，而长期接触会使气孔反应变得迟缓。已表明，在同时接触SO₂和NOₓ的植物中，气孔对脱落酸（ABA）的反应较慢，这表明对保卫细胞ABA信号转导有不利影响。此外，臭氧会导致干旱条件下气孔关闭减少。越来越多的证据表明空气污染物和氧化应激会对保卫细胞的钙稳态以及负责气孔运动的细胞内机制产生显著影响。在此，我们讨论空气污染物对气孔反应的影响及其对保卫细胞中基于钙的信号传导的可能影响，重点关注臭氧和氧化应激的影响。
