摘要
以叶绿素快相荧光动力学曲线(OJIP)为探针,研究了外源钙对干旱胁迫下烤烟幼苗光系统Ⅱ(PSⅡ)功能的影响.结果表明:干旱胁迫降低了烤烟幼苗PSⅡ原初光能转换效率(Fv/Fm)和电子传递速率(ETR),抑制了光合作用的原初过程,烤烟幼苗叶片发生了明显的光抑制.叶面喷施10.0mmol·L-1CaCl2溶液后烤烟叶片的光合电子传递能量比例(φEo)在干旱胁迫下的降低幅度明显小于对照(喷施清水),电子转运效率(ETo/RC)在干旱胁迫下明显高于对照.叶面喷施CaCl2溶液增加了PSⅡ捕获光能用于光合电子传递的比例、剩余有活性反应中心的效率和电子传递链中的能量传递,使烤烟叶片的光系统Ⅱ在干旱胁迫下保持相对较高的活性,从而提高了烤烟幼苗的抗旱能力.
Taking chlorophyll a fluorescence transient OJIP as the probe,this paper studied the effects of foliar spraying 10 mmol·L-1 of CaCl2 on the functions of photosystem Ⅱ（PSⅡ） in tobacco seedling leaves under drought stress.Drought stress decreased the conversion efficiency of PSⅡ primary light energy（Fv/Fm） and electron transport rate（ETR）,and inhibited the primal process of photosynthesis,resulting in an obvious photoinhibition.After the spraying of CaCl2,the decrement of quantum yield for electron transport（φEo） under drought stress was obviously lower,and the increment of electron transport efficiency of per reaction center（ETo /RC） was obviously higher,compared with those after the spraying of water.Foliar spraying CaCl2 increased the amount of PSⅡ-captured light energy used for photosynthesis electron transport,the efficiency of surplus active reaction center,as well as the energy transport in electron transport chain,making the PSⅡ remain relatively high activity under drought stress,and accordingly,the drought resistance of the tobacco seedlings was improved.
出处
《应用生态学报》
CAS
CSCD
北大核心
2011年第5期1195-1200,共6页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(30771746
31070307)
黑龙江省烟草专(2007
2009)资助
关键词
烤烟
外源钙
干旱胁迫
PSⅡ
光抑制
flue-cured tobacco
exogenous calcium
drought stress
photosystem Ⅱ
photoinhibition
