低温光抑制恢复过程中黄瓜叶片PSⅡ活性及其电子传递对PSⅠ的影响  

Effects of cucumber leaf's PSⅡ activity and electron transfer on its PSⅠ activity in recovery process after chilling-induced photoinhibition

作　　者：张子山[1] 杨程[1] 高辉远[1] 王未未[1] 孙学娟[1] 孟祥龙[1] 孟庆伟[1] 

机构地区：[1]山东农业大学生命科学学院作物生物学国家重点实验室,山东泰安271018

出　　处：《应用生态学报》2012年第4期1049-1054,共6页Chinese Journal of Applied Ecology

基　　金：国家重点基础研究发展计划项目(2009CB118500);国家自然科学基金项目(30671451;30571125)资助

摘　　要：以"津春4号"黄瓜为试材,通过测定黄瓜叶片叶绿素荧光快速诱导动力学曲线和对820nm光的吸收曲线,结合叶绿素荧光淬灭分析,研究低温光胁迫(4℃,200μmol·m-2·s-1)6h后,黄瓜叶片在常温(25℃)不同光强(0、15、200μmol·m-2·s-1)下PSⅠ和PSⅡ活性的恢复,以及恢复过程中PSⅠ与PSⅡ的相互作用.结果表明:低温光胁迫6h后,PSⅠ和PSⅡ发生不同程度的光抑制.在常温恢复阶段,PSⅡ活性快速恢复且对光强不敏感;PSⅠ活性在弱光下(15μmol·m-2·s-1)快速恢复,在较强光(200μmol·m-2·s-1)下恢复较慢.在低温光抑制恢复过程中,常温下PSⅡ活性恢复较快可能导致PSⅡ向PSⅠ的线性电子传递过快,进而抑制PSⅠ的活性恢复.因此,在进行黄瓜抗冷性育种时,不应该仅追求较高的PSⅡ抗性和较快的PSⅡ恢复速度,还应该注意两个光系统活性的协调.在生产中,应当在低温逆境发生及其之后较长一段时间内采取措施降低叶表面光照强度,以利于对植株光合机构的保护和光合活性的恢复.Taking Cucumis sativus L.（Jinchun No.4） as test material,through the determination of chlorophyll-a fluorescence transient and light absorbance at 820 nm,and in combining with chlorophyll quenching,this paper studied the recovery of cucumber leaf＇s PSⅠ and PSⅠ activities and the interactions between PSⅠ and PSⅡ in the recovery process at room temperature（25 ℃） and under different light intensities（0,15,and 200 μmol·m-2·s-1） after six hours of low temperature（4 ℃） and strong light（200 μmol·m-2·s-1） stress.Different extent of photoinhibition of the PSⅡ and PSⅠ occurred after the stress.During the recovery process at room temperature,the PSⅡ activity recovered quickly and was insensitive to light intensity,while the PSⅠ activity recovered quickly under weak light intensity（15 μmol·m-2·s-1） but slowly under strong light intensity（200 μmol·m-2·s-1）,suggesting that after the chilling-induced photoinhibition,the reduced electron transfer from PSⅡ to PSⅠ protected the PSⅠ from further inhibition,accelerating the recovery of PSⅠ activity.In the breeding of chilling-resistant species of cucumber,it should not only pursue the higher chilling-resistance of PSⅡ and faster recovery of PSⅡ after chilling-induced photoinhibition,but also pay more attention to the coordinating of PSⅠ and PSⅡ during and after the chilling-induced photoinhibition.In the culture of cucumber,after chilling happened,a practical method to reduce light intensity would help the recovery of cucumber leaf PSⅠ activity to protect the photosynthetic apparatus against photoinhibition.

关 键 词：黄瓜 低温光抑制 电子传递 PSⅠ PSⅡ 

分 类 号：S642.2[农业科学—蔬菜学]