两种常绿阔叶植物越冬光系统功能转变的特异性  

Specificity of photosystems function change of two kinds of overwintering broadleaf evergreen plants

作　　者：钟传飞[1,2] 张运涛[1] 武晓颖[3] 王桂霞[1] 董静[1] 王丽娜[1] 常琳琳[1] 高荣孚[2] 

机构地区：[1]北京市农林科学院林业果树研究所,北京100093 [2]北京林业大学生物科学与技术学院,北京100083 [3]中国科学院动物研究所,北京100101

出　　处：《生态学报》2012年第23期7483-7491,共9页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(31201579);北京市科技计划(Z111100056811035-2);北京市农业科技项目(20110125)

摘　　要：通过叶绿素荧光和P700氧化还原动力学同步测定,研究大叶黄杨(Euonymus japonicus)和锦熟黄杨(Buxus spervirens L.)的阳生叶和阴生叶在北京地区越冬进程,光系统Ⅱ(PSⅡ)和光系统Ⅰ(PSⅠ)功能转变机制的特异性。结果表明,入冬前0℃以上低温条件下,各叶片PSⅡ有效光量子效率Y(Ⅱ)(Effective quantum yield of PSⅡ)处于同一水平,但阳生叶Y(Ⅰ)(Effective quantum yield of PSⅠ)均高于阴生叶,同时各叶片Fo(Minimal fluorescence)和OJIP水平不完全相同:大叶黄杨两种叶片差异不显著,锦熟黄杨阳生叶显著低于其阴生叶;同步测定P700氧化还原变化表明,两种阴生叶在0—20 ms的P700氧化过程分两个阶段,尤其是锦熟黄杨2 ms后的氧化速率显著降低,而两种阳生叶0—20 ms基本保持同一氧化速率;两种阴生叶的两个光系统量子效率比Y(Ⅰ)/Y(Ⅱ)<1,两种阳生叶Y(Ⅰ)/Y(Ⅱ)=1。入冬后,各类叶片PSⅡ受到不同程度光抑制,而PSⅠ光量子效率Y(Ⅰ)均先增加后减小,Y(Ⅰ)/Y(Ⅱ)发生不同程度增加,Y(Ⅱ)和两个光系统的平衡能力均依次为锦熟黄杨阴生叶>锦熟黄杨阳生叶>大叶黄杨阴生叶>大叶黄杨阳生叶;冬季大叶黄杨阴生叶J相的相对强度高于锦熟黄杨阴生叶,而两种阳生叶OJIP动力学变化几乎消失;同步测定P700氧化还原变化表明,锦熟黄杨阴生叶2 ms即达到Pm(Maximal P700 change),其他叶片0—20 ms保持同一氧化速率,阳生叶Fo、P700氧化速率和Pm均低于阴生叶。返青后,各叶片两个光系统功能逐渐恢复。可见,冬季低温或低温强光逆境会导致阳生叶和阴生叶的两个光系统功能和互动机制发生不同转变。photoinhibition often occurs in winter for most evergreen plants, which is particularly true in sun leaves. Lots of photoprotective approaches could be induced to prevent from photodestruction for the plants. Photoinhibition and photoprotection mechanisms were studied much more on conifer tree species than broadleaves ones, and more in PS Ⅱ than PS Ⅰ. In this paper, two evergreen broadleaved plantstree species （Euonmymus japonicus and Buxus spervirens L. ）under different light environments were studied during winter. The two woody species were introduced from Beijing. Specificity of both photosystem Ⅱ （ PS Ⅱ ） and photosystem Ⅰ（ PS Ⅰ ） changes of the two subtropical areas to woody species werestudied using methods of synchro-monitoring chlorophyll fluorescence and P700 redox kinetics. The results were shown that the low temperature above 0% didn＇t inhibit the effective PS H yield Y（ Ⅱ） for each species at the end of October, while Fo and OJIP values of the sun leaves of Buxus spervirens L. were lower than those of the shade leaves. Meanwhile PT00 oxidization of the sun leaves of the two species kept at the same rate from 0ms to 20ms, but the oxidation rate of the shade leaves of the two species decreased after 2ms, particularly in Buxus spervirens L.. Under this case, Y（ Ⅰ ）/Y（ Ⅱ） ratio of the sun leaves for both two species were 1, while the values of the shade leaves for both two species of were lower than 1. During winter, PS Ⅱ photoinhibition occurred in almost all of the leaves for both species. The order of the Y（Ⅱ ） value from the highest one to the lowest one in winter were as following： shade leaves of Buxus spervirens L. , sun leaves of Buxus spervirens L. , shade leaves of Euonmymus japonicus and sun leaves of Euonmymus japonicus. Whereas both the relative efficiency of PSI and the ratio of Y（ Ⅰ ）/Y（Ⅱ） increased in winter. Low temperature led to disequilibrium between PSⅡand PSⅠ of shade leaves of Euonmymus japonicus, while combine

关 键 词：大叶黄杨 锦熟黄杨 光系统 越冬 光抑制 

分 类 号：S718.4[农业科学—林学]