不同生育时期玉米苞叶叶绿素荧光特性差异分析

以郑单958和农大364两个玉米品种为研究材料,对大田条件下不同生育时期玉米苞叶的叶绿素含量和叶绿素荧光动力学进行了比较分析.结果表明,不同生育时期玉米苞叶叶绿素含量呈先升后降的变化趋势,并在灌浆期达到最高值,且农大364苞叶的叶绿素降低速率要低于郑单958,这样有利于其保持更为持久的光合能力.不同生育时期玉米品种间苞叶叶绿素荧光参数(Fm、Fv、Fv/Fm、Fv/Fo等)的变化规律基本一致,郑单958高于农大364,说明郑单958苞叶反应中心活性较高,具有较高的电子传递速率,并且苞叶叶片开放的PSⅡ反应中心捕获激发能的效率高于后者.

Analysis on Chlorophyll Fluorescence of Husk Leaves of Maize at Different Growing Stages

Zhengdan 958 and Nongda 364 were adopted in this experiment,both contents of chlorophyll and chlorophyll fluorescence parameters of husk leaves of maize(Zea mays L.)varieties at different growing stages were comparatively studied in the field condition.The results showed that chlorophyll content of husk leaves increased at first and then decreased,and reached the peak value values at milk-filling stage.The degradation rate of chlorophyll in husk leaves of Nongda 364 was lower than that of Zhengdan 958 at different growing stages,which was helpful in keeping photosynthetic activities.It was shown that the same diurnal change trend of chlorophyll fluorescence parameters (Fm,Fv,Fv/Fm,Fv/Fo,etc.) between the two varieties at different stages.Zhengdan 958 had higher chlorophyll fluorescence parameters than Nongda 364,indicating that Zhengdan958 was higher than Nongda 364 in active of PSⅡ reaction center,rate of electron transport,efficiency of excitation energy captured by open PSⅡ reaction centers.