中文摘要：

黄土高原半干旱区雨养春小麦（Triticum aestivum L.）产量一直受到当地特殊环境条件制约,气孔导度和胞间CO2浓度的变化对于分析光合作用限制十分重要。因此,在大田自然条件下分析了春小麦气孔导度、胞间CO2浓度对环境因子的响应及其阈值,结果表明：1土壤温度、空气温度对气孔导度和胞间CO2浓度影响显著,温度与两生理指标成二次曲线关系,且在不同生育期、不同生理指标的最适温度不同,黄土高原最适温度较湿润地区低;2土壤湿度与气孔导度和胞间CO2浓度呈正相关,土壤湿度低,变化幅度小,更倾向于是一种气候背景;3空气湿度与气孔导度呈正相关,特别是灌浆期对春小麦具有较大的促进作用。抽穗期空气湿度与胞间CO2浓度呈负相关,灌浆期二者关系不显著;4不同生育期生理特征对环境因子的敏感性有较大差异。

英文摘要：

Since stomatal conductance and intercellular CO2 concentration are very important physiological characteristics,a field experiment was conducted to explore the response of stomatal conductance and intercellular CO2 concentration to meteorological factors. Spring wheat（ Triticum aestivum L.） was chosen for the heading and filling stage. Physiological characteristics（ stomatal conductance and intercellular CO2concentration） were measured by LI-6400 portable photosynthesis analyzer in vivo monitoring of plant.,measuring meteorological factors simultaneously. The results showed that the stomatal conductance was significantly positive related to relative air humidity,while the intercellular CO2 concentration was significantly negative related to air relative humidity. Stomatal conductance and soil temperature showed a quadratic relationship,the optimum temperature was 30 ℃ and 33 ℃ in heading and filling stage. The same trend was also showed between stomatal conductance and air temperature,intercellular CO2 concentration and soil temperature,intercellular CO2 concentration and air temperature,with the optimum temperature being different.