遮阴对金叶风箱果叶绿素荧光参数的影响

Effects of Shading on Chlorophyll Fluorescence Parameters of Physocarpus opulifolius ‘Lutein’

以3年生金叶风箱果为试材,通过对其进行不同遮阴(0%、30%、50%和80%)处理,探究不同遮阴条件下快速叶绿素荧光诱导动力学曲线及快速叶绿素荧光参数,旨在阐明遮阴对金叶风箱果快速叶绿素荧光特性的影响。结果表明,随遮阴度的增加,金叶风箱果叶片的最大荧光值(Fm)、最大光化学效率(Fv/Fm)以及PSII潜在活性(Fv/Fo)的值均显著增大;遮阴处理下,PSII反应中心用于电子传递的量子比率(φEo)提高,而用于热耗散的量子比率(φDo)降低;随遮阴度上升,反应中心吸收的光能(ABS/RC)下降,用于电子传递的能量(ETo/RC)显著上升,而用于热耗散的能量(DIo/RC)显著下降。可见,遮阴后金叶风箱果叶片吸收的光能减少,但为适应弱光环境,可通过提高PSII电子传递效率及降低热耗散的能量,进而提高对光能的利用。

The 3-year-old plants of Physocarpus opulifolius‘Lutein'were used to analyze the chlorophyll a fluorescence transient and parameter under different shading treatments that were 0%,30%,50%and 80%,and the purpose of this study was to elucidate the effect of shading on chlorophyll a fluorescence transient in Physocarpus opulifolius'Lutein'.The results showed that:with shading ratio increased,the maximum fluorescence (Fm),the maximum photochemical efficiency (Fv/Fm)and latent reactivity of PSII (Fv/Fo)of P.opulifolius‘Lutein'enhanced apparently;The value of φEo increased significantly and but the value of φDo decreased under shade treatments.In terms of PSII reaction center aspect,the value of ABS/RC decreased,the value of ETo/RC increased evidently,but the value of DIo/RC decreased dramaticlly with the degree of shading increased.Thus it can be seen under shade treatments,the P.opulifolius ‘Lutein'leaves had the reduced fluxes of absorption,but for the sake of adapting the weak light environment,it can improve the utilization of light energy by improving the efficiency of electron transfer in the PSII and reducing energy of dissipation.