抽穗后冬小麦旗叶光合特性的变化对产量的影响

Changes of Flag Leaf Photosynthetic Characteristics After Heading:Effect on Yield of Winter Wheat

为了探讨不同小麦品种之间的光合特性的差异及光合作用与经济产量的关系,本研究选取4个不同冬小麦品种分别在6个生育时期进行了光合特性的测定。结果表明:小麦旗叶6项光合特性指标随发育进程变化的趋势、变化程度基本相同,但不同品种在不同发育时期内光合特性指标的数值、变化程度不同;6项光合特性指标均与籽粒产量正相关;相关程度表现为绿叶面积>气孔导度>胞间CO2浓度>净光合速率>叶绿素含量>蒸腾速率;不同时期光合特性与籽粒产量的相关性顺序为灌浆中期>灌浆前期>灌浆后期>开花期>抽穗期>灌浆末期;在开花期至灌浆后期,维持和提高旗叶的绿叶面积、叶绿素含量、净光合速率、气孔导度、胞间CO2是提高小麦产量的基础。因此,在开展小麦高光效育种时,对种质资源材料进行光合特性测定和比较对育种工作具有非常重要的参考价值和指导意义。

To explore the differences of photosynthetic characteristics among different wheat varieties and the relationship between photosynthesis and economic yield,four different winter wheat varieties were selected to determine their photosynthetic characteristics in six growth periods.Results showed that:the change tendency and degree of six photosynthetic characteristic indexes of wheat flag leaf with the development process were basically the same,but the values and change degrees of photosynthetic characteristics of different varieties in different development periods were different.Six photosynthetic characteristic indexes were positively correlated with grain yield respectively.The order of the correlation degree was as following:green leaf area>stomatal conductance>intercellular CO2 concentration>net photosynthetic rate>chlorophyll content>transpiration rate.The order of correlation between photosynthetic characteristics and grain yield in different growth stages was middle grain filling stage>early grain filling stage>post grain filling stage>flowering stage>heading stage>end grain filling stage.It was the basis of increasing wheat yield to maintain and improve the green leaf area,chlorophyll content,net photosynthetic rate,stomatal conductance and intercellular CO2 of flag leaf from flowering stage to post filling stage.Therefore,it is of reference value and guiding significance to determine and compare the photosynthetic characteristics of germplasm resources in wheat breeding with high light efficiency.