冬麦春播条件下旗叶光合特性、叶绿素荧光参数变化及其与产量的关系

Flag leaf photosynthetic characteristics,change in chlorophyll fluorescence parameters,and their relationships with yield of winter wheat sowed in spring

以长江中下游、西南麦区的5个优良冬播小麦品种为材料,在忻定盆地春播（早播、适播）条件下,于2013-2014年对开花期、灌浆期的旗叶光合指标、叶绿素含量及叶绿素荧光参数进行测定,并分析这些参数与产量的相关性.结果表明：品种间大多荧光参数（除叶绿素外）差异显著,且相关性显著;叶绿素变异系数较小（0.12-0.17）,吸收光能为基础的性能指数（PIabs）变异系数较大（0.32-0.39）,两参数与产量偏相关系数为0.70-0.81;早播条件下,籽粒产量与PIabs（灌浆期、开花期）、灌浆期叶绿素呈显著正效应与灌浆期旗叶在I点的相对可变荧光强度（Vi）呈显著负效应,且产量的81.1%-82.8%（2013、2014年）可由这3因素的变异决定;不同品种表现出不同的播期效应,且两年变化趋势基本一致：扬麦13（春性、中早熟）旗叶光合速率、叶绿素及绝大多数荧光参数和产量均显著高于其他品种,且适宜早播.早播条件下灌浆期旗叶叶绿素含量、PIabs、光合速率可作为选择高光效小麦资源的重要评价指标.

With five good winter wheat cultivars selected from the middle and lower reaches of Yangtze River and Southwest China as test materials,a field experiment in Xinding basin area of Shanxi Province was conducted to study the photosynthetic characteristics,chlorophyll content,and chlorophyll fluorescence parameters of flag leaf at different sowing dates,as well as the correlations between these indices and yield for two years（2013-2014）.The results showed that the difference in most fluorescence parameters except chlorophyll content among cultivars was significant.The correlations between these fluorescence parameters and yield were significant.The variation coefficient of chlorophyll（Chl） content was low（0.12-0.17）,and that of performance index based on absorption（PIabs） was high（0.32-0.39）,with the partial correlation coefficients of them with grain yield from 2013 to 2014 ranged in 0.70-0.81.Under the early sowing condition,the grain yield positively correlated with PIabs at flowering and filling stages and chlorophyll content at grain filling stage,but negatively correlated with the relative variable fluorescence at I point（Vi） at grain filling stage.About 81.1%-82.8%of grain yield were determined by the variations of PIabs,Chl,and Vi.Wheat cultivars had various performances in the treatments with different sowing dates and a consistent trend was observed in the two experimental years.Among these 5 cultivars,Yangmai 13 was suitable for early sowing,with the flag leaf photosynthetic rate（Pn）,Chl,most fluorescence parameters,and grain yield showed obviously high levels.In conclusion,under early sowing condition chlorophyll content at grain filling stages,PIabs at flowering and filling stages,and Pn were important indices for selecting wheat cultivars with high photosynthetic efficiency.