小麦苗期叶片PSⅡ结构与功能对光胁迫的响应  

Effect of light stress on structure and function of PS Ⅱ in wheat(Triticum aestivum L.cv.Yangmai No.5)seedling leaves

作　　者：陈国祥[1] 张荣铣[2] 何兵[1] 魏锦城[1] 

机构地区：[1]南京师范大学生命科学学院,江苏南京210097 [2]南京农业大学农学院,江苏南京210095

出　　处：《农村生态环境》2003年第3期26-30,共5页Rural Eco-Environment

基　　金：国家重点基础研究发展规划项目 (G19980 10 10 0 )

摘　　要：以扬麦 5号苗期叶片的类囊体膜和PSⅡ颗粒为对象 ,测定光胁迫条件 (2 50 0 μmol·m- 2 ·s- 1 )下PSⅡ组分和功能特性的变化。光逆境条件下 ,类囊体膜及PSⅡ颗粒的放氧活性明显下降。室温下荧光发射光谱的测定结果也表明 ,光逆境处理导致类囊体膜及PSⅡ颗粒荧光发射强度下降。多肽组分变化的分析显示 ,PSⅡ颗粒外周蛋白OEC 33 0 0 0u多肽对光胁迫响应最为敏感 ,降解较显著 ,外周蛋白OEC 1 70 0 0、2 3 0 0Effects of light stress on function and structure characteristics of photosynthetic membranes (thylakoid membranes and PS Ⅱ particles) in leaves of wheat( Triticum aestivum L.cv.Yangmai No.5)seedling were studied by measuring changes in O 2 evolving activity,fluorescence emission spectra and membrane protein polypeptide components. Results showed that light stress (2 500 μmol·m -2 ·s -1 ) induced decline of electron transport activities of thylakoid membranes and PS Ⅱ particles and decrease in fluorescence emission intensities. When PS Ⅱ particles in wheat leaves were illuminated with higher light intensity (2 500 μmol· m -2 ·s -1 ) at 25 ℃, the extrinsic protein (OEC 33 000,23 000,17 000 u) and the chlorophyll binding protein CP43 of PS Ⅱ complex were degraded. It seems that OEC 33 000 u polypeptide plays a role in regulating stabilization of the PS Ⅱ reaction center structure under light stress.

关 键 词：扬麦5号 PSⅡ 光胁迫 放氧活性 荧光发射光谱 多肽组分 

分 类 号：S512.1[农业科学—作物学] Q945.78[生物学—植物学]