云锦杜鹃夏季气体交换和水分利用效率日变化  

Diurnal variation of gas exchange and water use efficiency of Rhododendron fortunei leaves in summer

作　　者：柯世省[1] 

机构地区：[1]台州学院生命科学学院,浙江临海317000

出　　处：《生物学杂志》2007年第4期37-40,61,共5页Journal of Biology

基　　金：浙江省自然科学基金资助项目(Y504256);浙江省教育厅科研计划资助项目(20030769)

摘　　要：云锦杜鹃净光合速率和气孔导度日变化曲线为"双峰"型,光合效率午间明显降低,主要由非气孔限制引起。表观量子效率和实际光化学效率的降低是非气孔限制形成和发展的深层原因。蒸腾速率的日变化为"单峰型",午间最高。水分利用效率早晚较高、午间较低。净光合速率、蒸腾速率、气孔导度和水分利用效率分别与一些环境因子的相关性达到0.01或0.05显著水平。利用多元逐步回归方法分别得到了净光合速率、胞间CO2浓度、蒸腾速率、气孔导度和水分利用效率与环境因子的最优方程。The diurnal variations of net photosynthetic rate （Pn）, transpiration rate （ Tr）, stomatal conductance （Gs） and water use efficiency （WUE） of Rhododendronfortunei leaves under natural conditions were studied. The results were as follows ： in summer clear days, the curves of diurnal variations of Pn and Gs had two peaks, which had an obvious phenomenon of midday decline of photosynthetic efficiency. The mid -depress of Pn was principally caused by non ＇stomatal limited elements. The decrease of AQY and actual photochemical efficiency （ φPS Ⅱ ） at noon showed that there existed photoinhibition, which was the intrinsic reason why non-stomatal limitation could form and develop. Tr had single peak which showed the maximum at noon. WUE was higher at sooner or later, and was lower at noon. The correlations, Pn, Tr, Gs and WUE to some environmental factors, were all significant at 0. 01 or 0. 05 probability level. The most excellent equation of the diurnal variation of Pn, Ci, Tr, Gs and WUE were attained by the methods of stepwise multi -regression respectivelv.

关 键 词：净光合速率 蒸腾速率 气孔导度 水分利用效率 日变化 云锦杜鹃 

分 类 号：Q945[生物学—植物学]