小麦单位面积产量取决于产量三因素：单位面积有效穗数、每穗粒数和粒重；实现对它们的优化调控对高产育种至关重要。小麦和水稻同属禾本科植物。虽然已有多个水稻产量因素 QTL被克隆，但是产量三因素形成和互作的遗传控制机制仍然不清楚。我们通过QTL和关联分析在小麦中确定了14个对产量三因素有显著影响的染色体区段。其中多个区段，如位于4BL和5AS上的QTL区段，影响多个性状。本项目拟在此基础上，进行小麦产量三因素QTL的精确定位和它们的等位变异及其遗传效应与互作关系的解析；确定这些QTL与水稻等物种中已知产量相关基因的同源关系并分析小麦同源基因的功能。有证据表明4BL和5AS上的QTL区段与已知产量相关基因不存在共线性关系。为此，本项目拟克隆这两个QTL并阐明其功能。上述研究将有助于解析小麦产量三因素形成的遗传控制机制，发掘优异的高产基因或等位变异，为小麦高产育种提供基因资源和理论基础。

The yield of grain crops is determined by three yield components, i.e., productive spikes per unit area, kernels per spike and kernel weight. Their coordination optimization is critical for high yield improvement. Both wheat and rice are Gramineae grain crops. Although dozens of yield component-related QTLs have been cloned in rice, the genetic control mechanisms underlying the formation and interactions of the three yield components are still not clear. In our previous studies, we have identified 14 chromosome regions in wheat showing significant association with the three components through QTL mapping and association analysis. Many of these regions, for example those located on chromosome 4BL and 5AS, affected multiple traits. In this study, we propose to precisely map these QTLs, investigate the genetic effects of their allelic variations and interactions, and characterize the collinear relationships of these wheat QTL intervals with known yield-related genes and the homologous wheat genes. Since our data indicated that the mentioned 4BL and 5AS QTLs might not be homologous to the known yield genes, we also propose to clone these two QTLs and characterize their functions. Through these studies, we aim at dissecting the genetic mechanisms underlying wheat yield component formation, exploring high yield-related new genes or allelic variations, eventually developing theoretical basis and genetic resources for high yield breeding.