【摘要】 目的:研究新疆鼠尾草叶片净光合速率日变化及与环境因子的关系。方法:利用LI-6400XT光合仪测定新疆鼠尾草叶片净光合速率,采用Excel 2003和Spass 13.0进行数据整理及作图和进行相关分析。结果:新疆鼠尾草叶片净光合速率、蒸腾速率日变化均呈现"双峰"曲线,有明显的光合"午休"现象;净光合速率峰值分别出现在12:00和18:00,分别为22.77和20.28μmol CO₂·m^-2·s^-1,第1峰值大于第2峰值;蒸腾速率的峰值分别出现在12:00和16:00,分别为13.02和13.09 mmol·m^-2·s^-1。午间14:00稍有下降,降至12.76 mmol·m^-2·s^-1;相关分析表明,新疆鼠尾草净光合速率与气孔导度呈极显著正相关（r=0.892）,与蒸腾速率呈显著正相关（r=0.835）,与田间CO₂浓度呈显著负相关（r=-0.849）;在有效光照强度、气温、空气湿度、田间CO₂浓度和蒸汽压差亏损5个环境因子中,田间CO₂浓度是影响净光合速率日变化的主要环境因子;在蒸腾速率、气孔导度、胞间CO₂浓度3个自身生理因子中,气孔导度是影响净光合速率日变化的主要自身生理因子;影响蒸腾作用的主要外在环境因素是有效光照强度,主要内在生理因素为气孔的自我调节因素。结论:通过研究新疆鼠尾草叶片净光合速率变化规律及与环境因子的关系,为其更好地开发利用奠定了生物学基础。更多还原

【Abstract】 Objective:To identify the relationship between diurnal changes of photosynthetic rate and environmental factors of Salvia deserta Schang（Salvia,Labiatae/Lamiaceae）.Methods:Photosynthetic characteristics were monitored using portable Li-6400XT photosynthesis system,and the data was processed by the Excel 2003 and Spass13.0.Results:The curves of diurnal variations in Pn（net photosynthetic rate） and Tr（transpiration rate） showed two peaks and an obvious midday depression.The Pn peaks were detected at 12;00 and 18;00,and reached to 22.77and 20.28 μmol CO₂·m^-2·s^-1,respectively;the first peak was higher than the second.The Tr peaks were detected at 12;00 and 16;00,and reached to 13.02 and 12.86 mmol·m^-2·s^-1,respectively.Pn was significantly positively correlated with Gs（stomatal conductance;r = 0.892）、Tr（r = 0.0.835） and significantly negatively correlated with Ca（field CO₂ concentration;r =-0.849）.Ca was the major environmental factor influencing diumal changes of the Pn during the five environmental factors,PAR（photosynthetically available radiation）、Ta（air temperature）、RH（relative humidity）、Ca and Vpd（deficit of water air pressure）;Gs was the major self-physical factor influencing diurnal changes of the Pn during the three factors,Tr、Gs and Ci（intercellular CO₂concentration）.PAR was the major environmental factor influencing diurnal changes of the Tr,Gs was the major self-physical factor.Conclusion;Provide the biological basis for further development and utilization of Salvia deserta Schang.更多还原