高温胁迫对无柄小叶榕光合作用的影响  

Effects of High Temperature Stress on Photosynthesis in Ficus concinna var. subsessilis

作　　者：金松恒[1] 李雪芹[2] 王俊刚[1] 

机构地区：[1]浙江林学院林业与生物技术学院,浙江临安311300 [2]浙江林学院天目学院,浙江临安311300

出　　处：《中国农学通报》2009年第3期83-87,共5页Chinese Agricultural Science Bulletin

基　　金：浙江省自然科学基金项目"Rubisco活化酶选择性剪接在植物高温抗性中的作用"(Y3080446)

摘　　要：以无柄小叶榕为材料,研究了不同时间高温处理对无柄小叶榕气体交换参数、叶绿素荧光参数和Rubisco活力的影响。结果表明,随着高温处理的持续,净光合速率(Pn)持续下降,而气孔导度(Gs)下降非常缓慢,蒸腾速率(Tr)则先开始快速上升随后保持稳定,但是胞间CO2浓度(Ci)却没有明显变化。进一步研究发现,在高温胁迫下,开放PSII反应中心激发能捕获效率(Fv'/Fm')、光化学猝灭(qP)、PSII实际量子产额(ФPSI)I和电子传递速率(ETR)都持续下降。Rubisco初始活力下降速度则快于这些荧光参数的变化。非光化学猝灭(NPQ)则是先迅速上升后来略有下降。这些结果表明高温抑制无柄小叶榕的光合作用不是由于气孔因素引起的,而是由于高温抑制了Rubisco活力,进而影响PSII活力和电子传递。We explored the gas exchange, chlorophyll fluorescence properties and Rubisco activity in Ficus concinna var. subsessilis under high temperature stress. The results showed that with continuing of high temperature, the net photosynthetic rate （Pn） in Ficus concinna was decreased, and the stomatal conductance （Gs） was slightly decreased. The transpiration rate （Tr） was increased after the 4 d of treatment, and then maintained stable, while the intercellular CO2 concentration （Ci） was rather stable. Further studies showed that the efficiency of energy conversion of open PS Ⅱ （Fv′/Fm′）, the actual efficiency of total PSⅡ centers （Фrsu）, photochemical quenching （qP）, and electron transport rate （ETR） were decreased. The magnitude of the decrease in these parameters was much less than that in the initial Rubisco activity. And the non-photochemical quenching （NPQ） were increased after the 12 d of high temperature stress, and then was slightly decreased. There results suggested that the decreased Pn under high temperature stress was not resulted from the decrease of stomatal conductance, and the primary limitation of Pn was suppression of Rubisco activity, thereby the PSⅡ activity and the electron transoort were decreased.

关 键 词：无柄小叶榕 高温胁迫 光合作用 Rubisco活力 

分 类 号：S718.43[农业科学—林学] Q945.11[生物学—植物学]