太湖源雷竹光合作用日变化规律研究

Study on the Diurnal Variations of Photosynthesis of Phyllostachys praecox

以太湖源雷竹为试材,采用Li-6400光合作用测定仪对太湖源雷竹的光合作用及其环境因子的日变化规律进行了测定,并利用SPSS 19.0对其重要参数进行了相关性分析。结果表明:太湖源雷竹的光合作用表现出较明显的日变化规律。净光合速率(Pn)和光合有效辐射(PAR)均呈"单峰"曲线变化,未出现光合"午休"现象。胞间CO2浓度的日变化呈"单峰"曲线,其变化趋势与光合作用速率呈相反变化规律,气孔限制值和蒸腾速率(Tr)的日变化也呈现"单峰"型曲线,气孔导度则呈现"双峰"型曲线变化规律。相关分析结果,表明对Pn影响最显著的因子是PAR,其次分别是气孔导度(Gs)、叶温下蒸气压亏损(VPD)、叶温(Tleaf)、气温(Tair)和空气相对湿度(RH);对Tr影响最显著的因子是Gs,其次是RH、PAR、Tair、Tleaf和VPD。

Taking Phyllostachys praecox as material, the photosynthesis and its environmental factors of diurnal course discipline of Taihuyuan Phyllostachys praecox were measured using Li-6400. Its important parameters of the correlation had been analyzed by SPSS 19.0 software. The results showed that the photosynthesis of Taihuyua~ PhyUostachys praecox showed a clear day change rule. Photosynthesis rate and photosynthetic active radiation were in ＇unimodal＇ curve changes, and there was no ＇ midday depression＇. Diurnal intercellular COz concentration was in ＇ unimodal＇ curve changes, and the change rule of photosynthesis rate was inverse relationship changes;transpiration rate and stomatal limitation of present day change was ＇unimodal＇ type, the stomatal conductance were revealed ＇bimodal＇ type rule changes. Correlation analysis results showed that the net photosynthetic rate （Pn） affected the most significantly with the factor PAR, followed by Gs, VPD, Tleaf, Tair and RH respectively; transpiration rate （Tr） affected the most significantly with the factor was Gs, second was RH,PAR,Tair ,Tleaf and VPD.