增强UV-B辐射对植物光能传递过程的影响

Effects of Ultraviolet-B Radiation on Plant Light Energy Transfer Process

为探讨增强的紫外线-B(280～315nm)辐射对光合作用原初光能传递的光物理过程的影响,对菠菜类囊体膜及光系统II的吸收光谱、稳态荧光发射谱进行了分析.结果显示在实验条件下(温室,紫外线-B施加于植物成熟期,紫外线-B剂量1.152kJ·m-2·d-1),增强紫外线-B辐射并没有抑制原初光能传递过程,植物通过一系列调节机制(增强吸收短波光色素的吸收强度,调节两个光系统间能量分配,变化光合系统中色素蛋白构象、位置)保证了原初光能传递的光物理过程,将能量传递到反应中心用于光合作用.

To clarify the effects of Ultraviolet-B （UV-B, 280-315 nm） treatment on the energy transfer process in photosynthesis, steady-state absorption and fluorescence techniques are performed on thylakoid membrane and photosystem II （PSII）.The results show that under greenhouse, lower UV-B radiation levels do not inhibit light energy transfer process. Plant ensures energy reach to reaction center through a series of adjustment mechanism. These mechanisms include enhancement of absorb intensity of short-wavelength-absorption pigments, regulation of energy distribution between two photosystems and the changs of conformation and （or） location about pigment-protein system.