小麦籽粒灌浆期冠层温度与产量相关性状的关系

为了揭示小麦冠层温度对产量作用的实质,探索小麦低温育种工作的技术路线,以18个小麦品种为材料,对籽粒灌浆各阶段的冠层温度和源库活性指标分别进行了主成分分析,并对二者之间的关系进行了相关分析,对冠层温度指数与产量构成因素的关系进行了通径分析和决策分析,对品种的产量结构进行了系统聚类分析。结果表明,小麦籽粒灌浆期冠层温度指数与各源库活性综合指标的相关系数均达到极显著水平;冠层温度指数与籽粒充实指数的直接通径系数和相关系数均达到显著负相关,而与潜在库容的直接通径系数和相关系数均未达到显著水平,各因素对籽粒充实指数的决定作用顺序为冠层温度指数>千粒库容>千粒重,各因素对潜在库容的决定作用顺序为千粒库容>单位面积穗数>穗粒数;参试品种被分为4类,各类之间的产量及产量结构差异明显。可见,小麦冠层温度主要通过籽粒充实指数间接作用于产量,低冠层温度和大潜在库容的优化组合是高产品种的重要特征。

Relation between wheat canopy temperature and traits related to yield in grain filling stage

To reveal the essentials of relation between wheat canopy temperature and yield,to research the technological route about cool wheat breeding,18 wheat cultivars were used as the experimental material to analyse canopy temperature and source-sink activity indices by analysis of principal component and their relation was tested by correlation analysis,and the relation between canopy temperature index and yield components was analysed by path analysis and decision analysis,and the yield structure was analysed by systematic claster analysis.The results showed that there were significant correlation coefficients between canopy temperature index and source-sink activity synthetical indices in grain-filling stage;direct path coefficient and correlation coefficient were significantly negative between canopy temperature index and kernel's filling index but were not significant between canopy temperature index and latent storage capacity.The importance order of factors for kernel's filling index was:canopy temperature index>1 000-grain storage capacity>1 000-grain weight;the importance order of factors for latent storage capacity was:1 000-grain storage capacity>ears per area>grains per ea;18 wheat cultivars were clustersed into 4 groups which were obvious diversity in yield and yield structure.Canopy temperature indirectly functioned in grain yield through kernel's filling index,the optimized combination of lower canopy temperature and bigger latent storage capacity was the important character of high yeild cultivars.