一氧化氮是脱落酸诱导杨树叶片气孔关闭的信号分子

研究了外源NO和ABA对杨树气孔运动调节作用．结果表明，外源NO和ABA都能诱导杨树离体叶片气孔关闭，且具有剂量效应，NO可加强ABA诱导气孔关闭的作用．NO清除剂(c—PTIO)可大大减弱NO和ABA对气孔关闭的诱导作用．证实了NO参与ABA调控气孔开闭运动过程，不同浓度NO供体SNP和ABA处理杨树离体叶片，SOD活性变化不明显，POD活性受到显著抑制．杨树叶片粗酶液的体外实验表明，不同浓度SNP对POD活性的抑制呈明显的浓度及时间效应；而ABA对POD活性则几乎没有影响．本研究证明，NO调节ABA诱导的树木气孔关闭作用，是ABA诱导树木气孔关闭的一种重要信号分子．

Nitric oxide,a signaling component of ABA-induced stomatal closure

The present study provided the evidence that exogenous NO and ABA regulated the stomatal movement in poplar leaves.It showed that different levels of SNP and ABA induced the stomatal closure in detached leaves.NO enhanced stomatal closure that induced by ABA.The effect of NO and ABA on stomatal closure was suppressed by c-PTIO,a specific NO scavenger.It was confirmed that NO involved in ABA-mediated stomatal movement.The activities of POD were dramatically inhibited,but those of SOD hardly decreased in different levels of SNP and ABA treatment.However,in vitro experiments indicated that the activities of POD were dramatically inhibited by NO,but not ABA.The results demonstrated that NO mediated ABA-induced stomatal closure of trees,and was a signaling component of ABA-induced stomatal closure.