中国农业科学2011，Vol.44Issue(15)：3118-3126,9.
镉对玉米叶片光系统活性的影响
Effect of Cadmium on Photosystem Activities of Maize(Zea mays L.)Leaves
摘要
Abstract
[Objective] The effect of Cd on photosystem activities of maize leaves, and the action site and ways of Cd to photosynthesis were studied in order to provide a theoretical foundation for understanding of the injury mechanisms of Cd to the photosynthetic apparatus. [Method] Two maize varieties were chosen as materials. One is the common variety mainly planted in northern China, Zhengdan 958 (ZD958). Another is a new variety with higher yielding potential, Denghai 661 (DH661). Maize seedling was continuously cultured with different Hoagland's solution containing 0, 10, 30 and 60 umol·L-1 of CdSO4 after 3-leaf-stage. After 40 days of treatment, the parameters of gas exchange, chlorophyll a fluorescence transient and light absorbance at 820 nm of maize leaves were measured for analying the injury reason of Cd to the photosynthetic apparatus. [ Result ] It was found that the declines of Pn were not mainly related to stomatic factors under Cd stress. After Cd treatment, both fluorescence at K-step (Wk) of PS II electron donor side and the fluorescence at J-step (Vj) of acceptor side were increased. However, the decrease of activity of electron donor side was lager than the electron acceptor side, which caused the decline of Ψo.With the increase of Cd concentration, the activity of RUBP (Ribulose 1,5-Biphosphate) decreased significantly, the utilization rate of NADPH was also decreased. They caused the electron accumulation in PS I increased and the 820 nm light absorption of PS I (△IR/Io) decrease. And then, which caused the activity declined of PS II was not in keeping with PS I , thus depressed the coordination between PS II and PS I (Φ(PSI/PS)). [Conclusion] Under the Cd stress, the main reason of Pn declined was not caused by non-stomata limitation. Cd decreased the activity of PS II electron donor side, which resulted in the performance of PS II declined and reduced the amount of electron transport to PS I . The most importantly, the increased amount of electron accumulation in PS I fed back by the carboxylation system was more than the decreased amount of electron transport form PS II that resulted in the PS I performance declined sharply, which depressed the coordination of PS II and PS I , and caused Pn declining.关键词
玉米/Cd/叶绿素荧光/光系统性能/RuBP羧化酶活性Key words
maize/Cd/chlorophyll fluorescence/ photosynthetic performance/ RuBPcase activity引用本文复制引用
李耕,张善平,刘鹏,高辉远,王敬锋,刘晨旭,董树亭,张吉旺..镉对玉米叶片光系统活性的影响[J].中国农业科学,2011,44(15):3118-3126,9.基金项目
国家白然科学基金项目(31071358,30871476)、欧盟FP7国际合作项目(222645)、国家"十二五"科技支撑计划(2011BAD16B14)、山东省财政支持农业重大应用技术创新课题(2010) （31071358,30871476）
