高温胁迫对光系统Ⅱ异质性的影响  

EFFECTS OF HIGH TEMPERATURE STRESS ON THE HETEROGENEITY OF PHOTOSYSTEM Ⅱ

作　　者：温晓刚[1] 林世青[1] 匡廷云[1] 

机构地区：[1]中国科学院植物研究所

出　　处：《生物物理学报》1996年第4期714-718,共5页Acta Biophysica Sinica

摘　　要：高温胁迫可诱导光系统Ⅱ（ＰＳⅡ）活性中心转化为无活性中心。本文讨论了在高温胁迫导致荧光猝灭的情况下如何用叶绿素荧光动力学计算ＰＳⅡ无活性中心相对含量的问题。正常的小麦叶片其ＰＳⅡ无活性中心相对含量（Ｆｖｉ／ＦＶ）约为０．１５５±０．０１１。小麦叶片经５０℃１分钟高温胁迫后，其Ｆｖｉ（相对于正常Ｆｖ）降至对照的７０％，在随后室温下６０分钟内又降至５０％。而５５℃５分钟和５５℃１０分钟高温胁迫后，在恢复期内其ＰＳⅡ无活性中心的含量从常温的１．４倍左右的基础上分别上升至２．４和２．９倍，说明高温胁迫对ＰＳⅡ中心除了起瞬时钝化作用外，还存在一个间接的较为缓慢的持续钝化作用。The active PSⅡ reaction centers can be transformed into the inactive ones by high temperature stress. The problem how to calculate the inactive PSⅡ reaction centers with chlorophyll fluorescence kinetics under fluorescence quenching condition induced by high temperature stress was discussed. The relative content of the inactive PS Ⅱ reaction centers in normal wheat leaves was 0. 155±0. 011 calculated by Fvi/Fv.After treatment of 50℃ for 1 minute, Fvi (relative to normal Fv) decreased to 70% and further reduced to about half of its control during following readaptation to room temperature in 60 minutes. In contrast, in 55℃ treatment for 5 and 10 minutes, it was increased to about 140% of the control, and was further increased to about 240% and 290%, resp. after following readaptation to room temperature in 60 minutes. Thus in the inactivation of the PSⅡ reaction centers, a slow, indirect process was induced by high temperature stress, in addition to a prompt, direct action.

关 键 词：光合作用 光系统Ⅱ 异质性 叶绿素 高温胁迫 

分 类 号：Q945.11[生物学—植物学]