外源ABA、NO和H_2O_2对葱莲花瓣及叶片表皮气孔开闭的影响

Effects of Exogenous Abscisic Acid,Nitric Oxide and Hydrogen Peroxide on Stomatal Movement in Petals and Leaves of Zephyranthes candida

以葱莲(Zephyranthes candida)为材料,研究不同浓度外源脱落酸、硝普钠(sodium nitroprusside,SNP)及过氧化氢对花瓣和叶片表皮气孔开闭的影响,以期为三者在切花保鲜中的应用提供新的依据。实验结果表明,10～1000μmol/L脱落酸和硝普钠均能不同程度地引起花瓣和叶片表皮气孔关闭,且花瓣气孔较叶片气孔有更高的敏感性。过氧化氢对叶片表皮气孔开闭的影响大于对花瓣气孔的影响,花瓣表皮的气孔孔径仅在1000μmol/L处理时变化显著。这说明在外源信号物质延缓切花衰老的过程中,花瓣表皮气孔的运动也可能起到了一定的作用。适当外源信号物质处理能诱导花瓣表皮气孔关闭,从而使花瓣的蒸腾作用减小,维持植物体内水势,延缓切花衰老。

To illustrate the effect of ABA,SNP（sodium nitroprusside） and H2O2 on stomata in the petals and leaves of Zephyranthes candida and explain the application of endogenous signal substances in cut flower perservation,the rate of change in stomatal apertures was measured.Results showed that 10-1000 μmol/L SNP and ABA could induce different degrees of stomatal closure in petals and leaves,with stomata in petals having higher sensitivity than that in leaves.When undergoing H2O2 treatments,stomata in petals were only affected at 1000 μmol/L less sensitive than that in leaves.These results revealed that the movement of stomata in petals may help delay flower senescence when flowers undergo exogenous hormone treatments.Appropriate exogenous ABA and SNP treatment could delay flower senescence by inducing the closure of petal stomata,reducing the transpiration rate of petals,and maintaining the water potential of plant cells.