遮光对花叶细辛光合特性和荧光参数的影响

Effects of Photosynthetic Characters and ChlorophyⅡ Fluorescence Parameters on A.splendens under Different Sun-shading Treatments

探讨了在遮光度为 4 3 %、70 %、95 %的 3种遮光处理条件下 ,花叶细辛叶片的叶绿素含量及比值、净光合速率日变化、光 -光响应曲线、叶绿素a荧光参数Fv/Fm和Fv/Fo的变化。结果表明 :随遮光度增加 ,叶绿素a +b和叶绿素b含量增加 ,叶绿素a/b降低 ;绝对光能利用效率增加 ;最大净光合速率、光补偿点、光饱和点、暗呼吸速率降低。 4 3 %和 70 %遮光处理条件下 ,净光合速率日变化呈“双峰”型 ,而 95 %遮光处理条件下呈“单峰”型 ;叶绿素a荧光参数Fv/Fm和Fv/Fo值在 4 3 %和 70 %遮光处理条件下差异不显著 ,而在 95

Changes of partial physiology parameters including chlorophyⅡ contain, chl.a/b, the diurnal variation of photosynthesis, light-light response curves and chlorophyⅡ fluorescence parameters (Fv/Fm and Fv/Fo) of A.splendens were searched with different sun-shading treatments (43%, 70%, 95% sun-shading) in this paper. The results show that the containing of chlorophyⅡ and light utilization efficiency increase with the increasing of sun-shading, while MNPR Pn, LCP, LSP and Rd fall; diurnal variation of net photosynthetic rate presents two peaks under 43% and 70% sun-shading treatments, while there is only one peak with 95% sun-shading treatment. The study also shows that the chlorophyⅡ fluorescence parameters (Fv/Fm and Fv/Fo) have no significantly difference with 43% and 70% sun-shading treatments, while it is increases significantly with 95% sun-shading treatment.