油茶优良无性系光合作用的日变化

以油茶优良无性系“湘林67”为试材，采用LI-6400P便携式光合测定系统对其净光合速率（Pn）、蒸腾速率(Tr)等日变化规律及其影响因子进行了研究。结果表明:(1)上、下部叶片的净光合速率为宽大的单峰型，无光合午休现象；（2）上、下部叶片的蒸腾速率为典型的单峰型，水分利用效率为双峰型；（3）影响净光合速率的主要因子为光合有效辐射、参比室H2O浓度、参比室CO2浓度及胞间CO2浓度，影响蒸腾速率的主要因子为相对湿度、气孔导度、光合有效辐射、胞间CO2浓度及叶面饱和水汽压亏缺。

Diurnal Variation of Photosynthesis in Superior Clones of Camellia oleifera

Taking Camellia oleifera superior clone “XL67” as materials and using the Li-6400 portable photosynthesis system, diurnal dynamics of net photosythetic rate (Pn), transpiration rate(Tr), and impact factors of Pn and Tr were researched in this paper.The results showed that:(1) Diurnal variation of net photosynthetic rate (Pn) presented a single peak curve, and no midday depression existed;(2) The diurnal variation curve of transpiration rate presented a single peak curve and the diurnal variation curve of WUE presented a double peak curve;(3) Through multiple regression analysis ,it was showed that the main factors which influenced Pn were PAR、H2OR、CO2Rand Ci, and Cond was the main factor for medium-yield variety, and Tr were mainly influenced by RH、Cond 、PAR、Ci and Vpdl.