【摘要】 小麦(Triticum aestivum)粒重遗传力高、表型稳定，高产育种过程中对粒重的选择效果显著。本研究在前期基因定位的基础上，获得了多环境稳定粒重QTL-qTkw-2D，且该位点在多个群体中被报道。本研究利用与qTkw-2D紧密连锁的分子标记Xcfd233对3 000份育种高代系进行筛选，结合Wheat660K SNP芯片分型，在’科农2011’的F6代获得了qTkw-2D近等基因系。通过对近等基因系籽粒切片的皮层细胞大小分析，明确了qTkw-2D主要通过影响皮层细胞大小影响粒宽。灌浆速率分析结果显示，q Tkw-2D主要通过影响中后期灌浆速率影响粒重。对近等基因系多年多地单株及小区水平的粒重和产量进行分析，明确了qTkw-2D位点A单倍型可稳定增加粒重，且在歉收环境对小麦稳产具有重要意义。本研究为小麦粒重遗传改良和粒重功能基因挖掘提供了参考。更多还原

【Abstract】 In wheat(Triticum aestivum), grain weight selecting is effective for improvement of grain yield as its high heredity and stable phenotype. In previous study, a stable QTL for grain weight, q Tkw-2D, was identified and this QTL has been verified in several populations. In this study, the linkage marker Xcfd233 and Wheat660K SNP array were used to scan 3 000 high generation of breeding population. Finally, near isogenic lines(NILs) of qTkw-2D were achieved in the F6generation of ’Kenong 2011’. By comparison the pericarp cells size of the grain slices from two NILs, it was confirmed that qTkw-2D mainly affected grain width by affecting the size of inner pericarp cells. The analysis results of filling rate showed that q Tkw-2D mainly affected grain weight by affecting the grain filling rate during middle and late filling stage. The grain weight in different environments at individual and population level of NILs indicated that qTkw-2D influenced grain yield in both levels and haplotype A was of great importance to maintain grain yield during poor harvest environments. This study provides reference for grain weight improvement and function gene cloning.更多还原