三种木质藤本植物光合特性比较研究

Photosynthetic Characteristics of Three Woody Vines

随着城市化进程的加快,园林绿化面积愈来愈少,因此充分利用藤本植物进行垂直绿化,成为了拓展城市绿化空间、改善城市生态环境的重要途径。光合作用是植物体内最重要的代谢过程,不同植物的光合能力对其生长、产量及抗逆性都具有十分重要的影响,但目前对城市园林常用木质藤本植物光合特性方面的研究甚少。本研究采用LI-6400便携式光合作用分析系统,针对城市园林常用的3种木质藤本植物——忍冬(Lonicera japonica Thunb.)、五叶地锦(Parthenocissus quinquefolia Planch.)和地锦(Parthenocissus tricuspidata),开展其光合特性的比较研究,探讨这3种木质藤本植物对环境的适应性及其光合能力的差异,旨在为藤本植物在城市园林绿化中的合理应用提供理论依据。结果表明:3种木质藤本植物在净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)、蒸腾速率(Tr)、水分利用效率(WUE)和羧化效率(CE)之间有较为明显的差异。在相同的自然条件下,忍冬的净光合速率(Pn,平均值为13.55μmol·m-2·s-1)、气孔导度(Gs,平均值为5.94×10-2μmol·m-2·s-1)、胞间CO2浓度(Ci,平均值为345.00μmol·mol-1)、水分利用效率(WUE,其值为10.27 mmol·mol-1)和羧化效率(CE,其值为3.93×10-2 mmol·mol-1)等光合参数均高于五叶地锦和地锦。五叶地锦的净光合速率(Pn)、水分利用效率(WUE)和羧化效率(CE)均高于地锦。蒸腾速率(Tr)最大的为地锦,其平均值为1.68 mmol·m-2·s-1,而忍冬和五叶地锦的平均值分别为1.35和1.10 mmol·m-2·s-1。

With urbanization growing rapidly,green space is very limited,and the good application of vertical greening vines has become an important way to expand urban green space and improve the urban environment.Photosynthesis is the most important metabolic processes in plants,and the photosynthetic ability of different plants has an important effect on the growth,yield and resistance.In the study,the main photosynthetic parameters of three woody vines（Lonicera japonica Thunb.,Parthenocissus quinquefolia Planch and Parthenocissus tricuspidata） common in urban greening were investigated by LI-6400 portable photosynthesis system.The differences of environmental adaptability and photosynthetic ability were discussed,which will provide theoretical basis for reasonable application of vine plants in urban greening.The results showed net photosynthetic rate（Pn）,stomatal conductance（Gs）,intercellular CO2 concentration（Ci）,transpiration rate（Tr）,water use efficiency（WUE） and carboxylation efficiency（CE） of the three woody vines had significant difference.Under the same natural condition,Pn（13.55 μmol·m^-2·s^-1,Gs（5.94×10^-2 μmol·m^-2·s^-1,Ci（345.00 μmol·mol^-1）,WUE（10.27 mmol·mol^-1） and CE（3.93×10^-2 mmol·mol-1） of Lonicera japonica Thunb.were higher than that of Parthenocissus quinquefolia Planch and Parthenocissus tricuspidata.Pn,WUE and CE of Parthenocissus quinquefolia Planch were higher than Parthenocissus tricuspidata.Tr of Parthenocissus tricuspidata was the highest（1.68 mmol·m^-2·s^-1,and the Tr values of Lonicera japonica Thunb.and Parthenocissus quinquefolia Planch were 1.35 mmol·m^-2·s^-1and 1.10 mmol·m^-2·s^-1respectively.