桂花光合特性的光温响应  

Photosynthetic Response of Osmanthus fragrans to Light Intensity and Temperature

作　　者：柯世省[1] 

机构地区：[1]台州学院生命科学学院,中国浙江临海317000

出　　处：《生命科学研究》2007年第2期110-115,共6页Life Science Research

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：对丹桂光合特性光温响应的研究结果表明:1)净光合速率最适温度为24～28℃,在22～42℃之间,净光合速率、胞间CO2浓度、气孔导度和水分利用效率与温度的关系为二次多项式方程,暗呼吸速率和蒸腾速率与温度成线性关系;2)在控制条件下,随着温度的升高,光补偿点升高,光饱和点、表观量子效率、最大净光合速率下降.在自然条件下,丹桂光合日进程出现明显的光合“午休”,“午休”主要由非气孔限制引起,表观量子效率和光化学效率下降表明光抑制是午间非气孔限制形成和发展的深层原因.Mature leaves of 5-year-old potted Osrnanthus fragrans var. aurantiacus Mak. were used to determine the net photosynthetic rate （Pn）,intercellular CO2 concentration （Ci）,dark respiration rate （Rd）,transpiration rate （Tr）, water use efficiency （WUE） and stomatal conductance （Cs） in response to light intensity and temperature. Optimal temperature for Pn was 24-28℃.There was a second degree polynomial equation between Pn （or Ci,WUE and Cs） and temperature at 22-42 ℃ ,and a linear relationship between Rd （or Tr） and temperature. By controlled temperature at 27 ℃ ,31 ℃ and 39 ℃ ,highest light saturation point（LSP）, apparent quantum yield （AQY） and Pmax appeared in the plant at 27℃ ,but they were contrary at 39℃. Light compensation point （LCP） increased obviously and photoinhibition aggravated at 39℃. There existed an obvious decline of Pn at noon under nature condition in summer.The mid-depress of Pn was principally caused by non-stomatal limitation. The decrease of AQY and the efficiency of open reaction centers（ Fv′/ Fm′） at noon showed that there existed photoinhibition, which was the intrinsic reason why non-stomatal limitation could form and develop. It is suggested that mild shading culture of Osrnanthus fragrans var. aurantiacus Mak. is beneficial to the reduction of leaf temperature and photoinhibition in the summer.

关 键 词：光合特性 气体交换 叶绿素荧光 温度响应 光响应 丹桂 

分 类 号：Q948[生物学—植物学]