大叶女贞无气孔角质膜的水分渗透性研究

摘要

植物叶表角质层是植物防止水分流失和污染物进入叶内最主要的障碍层. 为了了解城市环境下绿化植物的叶角质层水分渗透性能,以西安市常见绿化植物大叶女贞( Ligustrum lucidum Ait. )为对象,采用草酸/草酸铵方法剥离了叶片的无气孔角质层,利用微蒸腾室法初步研究了水分渗透性能,并计算了其热力学活化能. 大叶女贞叶角质层在25℃和35℃下的水分渗透性分别为8. 03 × 10 -8和6. 66 × 10 -7 m/s,其热力学活化能为160. 5 kJ/mol. 渗透性随温度升高的原因可能是由于温度对角质膜表层蜡质晶体结构和连续性的影响.%The plant cuticle is a key barrier to prevent water loss and contaminants contacting and harming plant. In order to under-stand the leaf cuticle water permeability of green plants under the urban environment with complex air pollution, the water permeability of Ligustrum ( Ligustrum lucidum Ait. ) leaves that is the common green paper plant in Xi'an was researched. The astomatous cuticular membranes was isolated by 1:1 oxalic acid / ammonium oxalate solution, the water permeability was measured by micro-transpiration chamber, and the thermodynamic activation energy was calculated. The astomatous cuticular membrane water permeabilities of Ligus-trum are 8. 03 × 10 -8 and 6. 66 × 10 -7 m/s, respectively, for 25 ℃ and 35 ℃ condition, and the thermodynamic activation energy of water penetrate is 160. 5 kJ/mol. The reason for water permeability with temperature increasing may be due to temperature effects on the crystal structure of waxy cuticle surface and its continuity.