摘要
对翅果油树叶片净光合速率日变化进行了测定,并分析其与蒸腾速率、胞间CO_2浓度等光合参数及环境因子的关系。结果表明:翅果油树叶片净光合速率日变化呈"双峰"曲线,具有明显的光合"午休"现象,最高峰分别出现在9:00和15:00,变化范围在1.25~11.35μmol·m^(-2)·s^(-1)之间;11:00~12:00引起净光合速率降低的主要因素是气孔限制因素,9:00~11:00、15:00~19:00则为非气孔限制因素。净光合速率与光合参数的关系在一天中不同时段表现不同,6:00~9:00、15:00~19:00叶片净光合速率与蒸腾速率和气孔导度呈极显著正相关,与胞间CO_2浓度呈极显著负相关;9:00~12:00叶片净光合速率与胞间CO_2浓度、气孔导度分别呈显著和极显著正相关,与蒸腾速率呈不显著负相关;12:00~15:00叶片净光合速率与蒸腾速率和气孔导度呈显著正相关,而与胞间CO_2浓度呈不显著正相关。6:00~9:00影响叶片净光合速率的主要环境因子及其作用大小为光合有效辐射>胞间CO_2浓度,且前者表现为正效应,后者表现为负效应;9:00~12:00为光合有效辐射>空气CO_2浓度,且前者表现为负效应,后者表现为正效应;12:00~15:00为空气相对湿度,表现为正效应;15:00~19:00为光合有效辐射>空气温度,两者均表现为正效应。
Diurnal variation in net photosynthetic rate （Pn） of Elaeagnus mollis Diels leaf was measured and the relationships between Pn and the photosynthetic parameters of transpiration rate （Tr）, intercellular CO2 concentration （Ci）, stomatal conductance （Gs） and environmental factors analyzed. The results indicate that diurnal variation in Pn exhibits a dual-peak curve ranging between 1.25 - 11.35 μmol ·m^-2 · s^-1. The curve has an obvious midday depression, with the dual peak occurring at 9：00 and 15：00 respec- tively. Decline in Pn during 11：00 - 12：00 is caused by stomatal limitation factor, but by non-stomatal limitation factors during 9：00 11：00 and 15：00 - 19：00. The relationship between Pn and photosynthetic parameters varies with time during the day. 6：00 - 9：00 and 15：00 - 19：00, Pn exhibits a significantly positive correlation with Tr and Gs, but a significantly negative correlation with Ci. 9：00 - 12：00, Pn shows a significantly positive correlation with Ci and Gs, and a negative correlation with Tr. 12：00 - 15：00, Pn is significantly positively correlated with Tr and Gs, while it is positively correlated with Ci. The main environmental factors and their degree of influence on Pn are photosynthetically active radiation （PAR, positive effect） 〉 Ci （negative effect） during 6：00 - 9：00; PAR （negative effect） 〉 Ca （atmospheric CO2 concentration, positive effect） during 9：00 -12：00; relative humidtty （RH, positive effect） during 12：00 -15：00; and PAR 〉 Ta （atmospheric temperature, both positive effect） during 15：00 - 19： 00.
出处
《中国生态农业学报》
CAS
CSCD
北大核心
2009年第3期474-478,共5页
Chinese Journal of Eco-Agriculture
基金
山西高校科技研究开发项目(200611015)资助
关键词
翅果油树
净光合速率
蒸腾速率
气孔导度
胞间
CO2
浓度
环境因子
Elaeagnus mollis Diels, Net photosynthetic rate, Transpiration rate, Stomatal conductivity, Intercellular CO2concentration, Environmental factor
