激动素和丁二酸拌种对玉米衰老过程中叶绿体结构和叶绿素荧光参数的影响

为探明外源激动素（KT）和丁二酸（SUA）对叶绿体结构和功能特性的影响，以郑单958（晚衰型品种）和豫单2002（早衰型品种）为材料，采用盆栽试验，研究了0.00003 mg/kg的KT和300 mg/kg SUA复合剂进行拌种处理后叶绿体超微结构和荧光参数的变化。结果表明， KT和SUA拌种能明显抑制嗜锇颗粒的增加，防止基粒片层的扩张，从而维持了叶绿体结构的稳定性，表现出叶绿素(Chl)水平、 类胡萝卜素含量 (Car)及Chl a/b比值的增加; KT和SUA还能提高玉米生育后期叶片的光合效率，郑单 958和豫单 2002在1/2叶尖枯黄时的Fv/Fm和PSII值分别比对照提高7.8%和6.2%、 10.2%和2.7%，qP和qN值有所降低，从而调节PSII反应中心的开放，以减少热耗散利于延长叶片光合功能持续期。

Effects of kinetin and succinic acid seed dressing on the ultrastructure of chloroplasts and chlorophyll fluorescence parameters in aging process of maize

 In order to investigate the effects of kinetin (KT) and succinic acid (SUA) on the chloroplasts ultrastructure and function, the ultrastructure of chloroplasts and chlorophyll (Chl) fluorescence characteristics were studied for two genotypes with KT and SUA seed dressing under pot experiment. The results showed that KT and SUA inhibited the production of osmioplilic granules in order to maintain the structure of granum thylakoid integrity, which resulted in the increase of the chlorophyll and car content, the ratio of Chl a/b. KT and SUA also promoted the Fv/Fm and ΦPSII values by 7.8% and 6.2%, 10.2% and 2.7% at the 1/2 leaf yellow stage of Zhengdan 958 and Yudan 2002, but reduced the qN and qP values. Compared with Yudan 2002, normal senescence variety Zhengdan 958 was more excellent on the chloroplasts ultrastructure, chlorophyll content and fluorescence characteristics.