【作者】 刘鹏；

【导师】 倪中福；

【作者基本信息】 中国农业大学 ， 作物遗传育种， 2005， 硕士

【摘要】 为扩大杂交小麦亲本的遗传基础,我们实验室构建了一个以国外小麦(主要是以国外普通小麦为主,包含一些我国的普通小麦)为主要血缘的轮回选择群体,创造出一批农艺性状优良的轮回选择后代材料。 本实验选用上述轮回选择群体中选育出的15份后代材料(两份斯卑尔脱早熟材料,13份普通小麦大穗大粒材料)以及5份我国北方冬麦区优良普通小麦,分别从其农艺性状表现、轮回选择后代材料与普通小麦品种杂种优势和SSR分子标记遗传距离三个层次探讨了利用轮回选择手段创建小麦杂种优势群的可能性。主要结果如下: 1.对15份轮回选择材料和5份普通小麦的株高、穗长、结实小穗数、单株穗数、主穗粒数、千粒重和单株产量7个农艺性状连续三年的考察结果表明,在所有考察的7个性状上,轮回选择后代材料与普通小麦品种这两个类群间均表现极显著差异。依据农艺性状,这两个类型的材料可以聚为不同类群。 2.以5份普通小麦与15份轮回选择后代材料按照NCII设计组配成75个杂交组合,连续三年对杂种F1代的株高、穗长、结实小穗数、单株穗数、主穗粒数、千粒重和单株产量7个农艺性状的分析结果表明,轮回选择后代材料与普通小麦之间存在较大的杂种优势。如轮回选择后代材料与普通小麦杂种单株产量优势的平均值可达21.34%,高于普通小麦品种间的杂种优势值,表明通过轮回选择可以大幅度提高普通小麦的杂种优势潜力。 3.利用Nei—li’s法计算了15份轮回选择材料和5份普通小麦品种的EST-SSR和Genomic-SSR分子标记遗传距离,通过遗传距离聚类结果发现,轮回选择材料和普通小麦各自单独聚为一类,表明两种SSR分子标记都能将来自不同类群的材料聚到一起,可以用作杂种优势群划分的有效工具。但SSR分子标记遗传距离与杂种F1性状以及杂种优势相关不显著,表明不能完全根据亲本SSR分子标记遗传距离预测杂种优势以及杂种表现。更多还原

【Abstract】 Recurrent selection has been broadly used for crop improvement in many crops. Fifteen wheat lines have been selected from 15 recurrent selection populations using the Tal male sterility. The agronomic traits performances of the 15 wheat lines and 5 wheat elite lines, together with the hybrid vigors between the two groups, were tested for three years in Beijing. The genetic distances (GD) between the two groups were determined by SSR and EST-SSR markers in order to evaluate the effects of creating new heterotic groups by recurrent selection. The main results obtained are as follows:1. The performances of seven agronimic traits on 15 recurrent selection lines and 5 wheat elite varieties showed distinct difference between the two groups. The recurrent selection lines and the wheat elite lines were grouped into two clusters.2. Higher yield per plant was observed on hybrids between the recurrent selection lines and the wheat elite lines than that of hybrids between wheat elite lines after testing 75 hybridized combinations (NCII design) between the 15 recurrent selection lines and 5 common wheat elite varieties, indicating potential use of recurrent selection on constructing wheat heterotic group.3. Cluster analysis results based on SSR and EST-SSR markers revealed that the 15 recurrent selection lines and 5 wheat elite varieties could be assigned to distinct groups, suggesting the SSR markers was a useful tool for assigning heterotic group. However, no significant correlations between the SSR GD and the F1 heterosis performance and SCA were observed indicating the limitation of using SSR GD to predict wheat heterosis in breeding program.更多还原