不同叶龄拟南芥荧光参数分析及对强光的响应

Analysis of chlorophyll fluorescence parameters in Arabidopsis thaliana leaves of different ages and its responses to strong light

采用叶绿素荧光图像分析系统,研究了野生型拟南芥(Wild Arabidopsis thaliana)Col-0不同叶龄叶片的荧光参数变化及对强光的响应。结果表明,随叶片趋于成熟或衰老,20 min暗适应的最大PSⅡ光化学量子效率(Fv/Fm),稳定作用光下的PSⅡ有效和实际光化学效率(Fv′/Fm′和ΦPSⅡ)以及光化学猝灭系数(q P)均呈降低趋势,而非光化学猝灭系数(NPQ)增加;但短期5 d的处理期间其变化都不明显。与低光强相比,强光处理时Fv/Fm,ΦPSⅡ,Fv′/Fm′和q P呈降低趋势而NPQ明显升高。说明不同发育阶段的叶片具有明显差异的光化学反应特性,强光下光抑制现象明显;NPQ增加说明拟南芥能通过非辐射的热能耗散途径消耗过多的激发能,从而能避免光合机构的继续伤害。

The changes of chlorophyll fluorescence parameters of different ages leaves and it responses to strong light were analyzed using CF imager in wild type Arabidopsis thaliana. The results indicated that Fv/ Fm ,ФPS II,Fv＇/Fm＇ and qP were all decreased when leaves become mature and elder,and NPQ were increased. There were no significant changes of all parameters during 5 days of development. Compared with 30 min low light treatment, after 60 min strong light irradiation, Fv/Fm, ФPS II , Fv＇/Fm＇and qP were all significantly increased and NPQ were significantly decreased. These results demonstrated that that there was significant difference among leaves of different ages and strong light could cause serious photoqnhibition. The plants can dissipate excited energy through no-radiated heat and avoid continue damage on photosynthetic function.