中文摘要：

【目的】研究不同光质对玉米叶片光合作用及光系统性能的影响,旨在探讨阴天条件下光质变化对玉米光合作用影响的生理机理。【方法】在大田条件下,以郑单958（ZD958）和先玉335（XY335）为供试材料,设置3种光质处理,分别为红色膜（R）、蓝色膜（B）和绿色膜（G）,以白色纱网模拟阴天作为对照（CK）,试验于2013年4—6月在黄淮海玉米技术创新中心进行。于6片完全展开叶时进行光质处理,10 d以后,利用快速叶绿素荧光和820 nm光吸收技术测定气体交换参数、快速叶绿素荧光动力学曲线及820 nm光吸收量的变化,分析光质对玉米叶片光合作用和光系统性能的作用方式。【结果】阴天和模拟阴天条件下,各波段辐射能所占比例基本与晴天一致,但各波段光的绝对量均显著下降,其中蓝紫光下降最多。3种色膜处理中,蓝膜在蓝紫光和紫外光（300—510 nm）下降最少,且所占比例较自然光显著增加。不同色膜处理后,XY335和ZD958净光合速率（Pn）均显著下降,下降幅度表现为绿膜（G）〉红膜（R）〉蓝膜（B）,XY335下降幅度为40.13%、32.68%和22.00%,ZD958为46.92%、37.69%、27.46%。与对照相比,各处理的气孔导度（Gs）显著下降,胞间CO2浓度（Ci）却显著上升。这说明,不同光质处理Pn下降是由非气孔因素引起的。除XY335在蓝膜下外,两玉米品种叶片不同色膜处理下捕获的激子将电子传递到电子传递链中QA下游的电子受体的概率（Ψo）和以吸收光能为基础的性能指数（PIABS）均显著下降,下降的程度表现为绿膜〉红膜〉蓝膜,说明除XY335在蓝膜下表现出品种特异性之外,在不同的色膜处理下PSⅡ的性能均受到明显抑制,且不同处理对PSⅡ反应中心电子受体侧之后的电子传递链性能的抑制作用更大。除XY335在蓝膜下外,两品种不同光质处理叶片供体侧性能（Wk）和受体侧性能（Vj）均显著降低,?

英文摘要：

[Objective] The effect of different light qualities on photosynthesis and photosystem of maize leaves was studied to explore the physiological mechanism of photosynthesis in cloudy. [ Method ] Two maize varieties were chosen as materials. Zhengdan 958 （ZD958） is a common variety mainly planted in northern China, and Xianyu 335 （XY335） is sweeping in the Northeast of China. The two varieties were planted in field at National Maize Technology Innovation Center of the Huanghuaihai Region. Four light quality treatments were designed, including red film （R）, green film （G）, blue film （B） and white gauze simulation on cloudy days as a control （CK） at the stage of V6. After 10 days of treatment, the parameters of gas exchange, chlorophyll a fluorescence transient and light absorbance at 820 nm of maize leaves were measured for analyzing the effects of different light qualities on photosynthesis and photosystem. [ Result ] The percent of radiant energy of different light wave bands in overall radiant energy was the same with sunny days in cloudy days and simulated-cloudy days, but its absolute amount were significantly declined and the reduction of blue-violet was the largest. Blue film＇s decline was minimum at 300-510 nm in the three films. On the other hand, the percent of radiant energy of blue film at 300-510 nm increased significantly than sunny days. The results showed that leaves net photosynthetic rate （Pn） of XY335 and ZD958 decreased significantly under green film, red film and blue film, and the decrease was 40.13%, 32.68%, 22.00% and 46.92%, 37.69%, 27.46%, respectively. Compared with the control, the stomatal conductance （Gs） decreased significantly, but intercellular CO2 concentration （Ci） increased significantly, which demonstrated that the declines of Pn were not mainly related to stomatic factors under different light qualities. The probability of that a trapped exciton the moves an electron further than QA by trapped exciton （To） and performance index （PIABs?