东北红豆杉幼苗光合和荧光特性对不同光照条件的响应  

Response of photosynthetic and fluorescence characteristics of Japanese yew seedlings to different light conditions.

作　　者：刘彤[1] 崔海娇[1] 吴淑杰[2] 祝佳媛[1] 周志强[3] 

机构地区：[1]东北林业大学生态研究中心 [2]东北林业大学理学院 [3]东北林业大学森林植物生态学教育部重点实验室

出　　处：《北京林业大学学报》2013年第3期65-70,共6页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(30870464)

摘　　要：以4年生东北红豆杉为材料,研究了全光照(FL)、50%全光照(L1)、30%全光照(L2)和15%全光照(L3)4种光照条件下东北红豆杉幼苗的光合作用和叶绿素荧光特性的差异。结果表明:L2条件下的叶绿素a、叶绿素b含量和总叶绿素含量都最高,全光照使幼苗叶绿素a、叶绿素b含量和总叶绿素含量都显著减少;L3条件下的叶绿素a/b值最低为2.203,显著低于正常值。3种遮荫条件下的东北红豆杉幼苗的光响应曲线趋势基本一致,随光合有效辐射(PAR)的增加净光合速率(Pn)先快速增加后趋于平缓,L2幼苗的Pn最高,L3次之,L1最低;FL幼苗在PAR>1000μmol/(m2·s)时Pn出现明显下降。L2条件下叶片最大净光合速率(Pmax)、平均净光合速率(Pa)、光饱和点(LSP)、表观量子效率(AQY)、气孔导度(Gs)最高,光补偿点(LCP)和暗呼吸速率(Rd)相对较低;FL条件下,LSP、AQY最低,LCP、Rd最高。FL条件下幼苗荧光参数与遮荫条件相比,初始荧光(F0)显著升高,最大荧光(Fm)、可变荧光(Fv)、PSⅡ潜在活性(Fv/F0)和PSⅡ原初光能转换效率(Fv/Fm)显著降低,非光化学猝灭系数(qN)略高,光化学猝灭系数(qP)和电子传递速率(ETR)略低;L2和L3条件下幼苗的叶绿素荧光参数相差不大,也都比L1适宜。结果表明,全光照破坏了幼苗的光合机构,30%左右的全光照条件对幼苗更适宜。Four-year-old Japanese yew seedlings were taken as experimental materials to study the photosynthetic and chlorophyll fluorescence characteristics under four light conditions, i.e. FL： full light; L1 ： 50% FL; L2： 30% FL; L3： 15% FL. The results showed that the contents of chlorophyll a, chlorophyll b and total chlorophyll under L2 condition were the highest, FL declined the contents of chlorophyll a, chlorophyll b and total chlorophyll significantly; the lowest value of chlorophyll a/b was 2. 203 when appeared under L3 condition, and it was significantly lower than the normal range. The trends of light response curve of photosynthesis of Japanese yew seedlings were basically consistent under three shade conditions, the net photosynthetic rate （Pn） increased rapidly and then slow down follow photosynthetically active radiation（PAR） enhanced, and Pn under L2 condition was the highest, then was under L3, that under L1 was the lowest; P~ under FL condition declined obviously when PAR 〉 1 000 μmol/（m2. s）. The maximum net photosynthetic rate （Pmax）, average net photosynthetic rate （Pa）, light saturation point （LSP）, apparent quantum yield （AQY） and the stomatal conductance （Gs） under L2 condition were the highest, while the light compensation （LCP） and the dark respiration Rd wererelatively low. LSP and AQY under FL condition were the lowest, while LCP and Rd were the highest. Compared with shade conditions, the fluorescence parameters basis fluorescence （ F0） under FL seedlings rose significantly, the maximum fluorescence （Fm） , variable fluorescence （Fv ） , potential activity of PS I1 （Fv/Fo） and the efficiency of solar energy conversion （Fv/Fm） reduced obviously, the non- photochemical quenching coefficient （qN） rose slightly, photochemical quenching coefficient （qP） and the electron transport rate （ETR） reduced slightly. The fluorescence parameters under L2 and L3 conditions had little difference. The fluorescence parameters appeared t

关 键 词：东北红豆杉 光照条件 光合作用 荧光特性 

分 类 号：S718.5[农业科学—林学]