Genomics-Assisted Analysis and Exploitation of Barley Diversity (ERA-PG 061)

在过去的大约10000年里，农作物通过驯化和选择性育种从它们的野生祖先进化而来。这一过程为育种者捕获了许多有用的基因等位基因，但不幸的是，许多其他潜在有用的等位基因也在这一过程中丢失。因此，有必要从野生环境中识别和招募新的等位基因，包括生态位适应、胁迫耐受性和形态发展，以在气候变化的情况下实现可持续的、环境友好的作物生产。关联遗传学方法通过建立在广泛的基因组学信息和详细的表型分析基础上，可能提供了实现这一目标的强有力的方法。不幸的是，全基因组关联作图在野生样品中需要数十万个基因连锁标记，由于在这些人群中的连锁不平衡水平低。我们提出了一个实验策略来克服这个问题，它利用了这样一个事实，即连锁不平衡在不同的人群中以显着不同的速度衰减。我们的方法将使用大麦作为一个范例，调查关联映射的有效性，从野生鉴定有用的基因等位基因。我们的第二个目标是招募这些新的有用的基因等位基因，到先进的回交育种程序来自野生大麦（H。spontaneum）种质和优良品种。这将使我们能够确定鉴定和提取有用的等位基因在大麦育种计划的基础上广泛的杂交效率。我们的第三个主要项目目标是利用项目中获得的大量DNA和标记数据集来确定大麦的重要群体遗传参数。

Crop plants have evolved from their wild ancestors through domestication and selective breeding over approximately the last 10 000 years. This process has captured many useful gene alleles for breeders but, unfortunately, many other potentially useful alleles have also been lost during this process. There is therefore a need to identify and recruit new alleles from the wild, including niche adaptation, stress tolerance and morphology development for sustainable, environmentally benign crop production in the face of climate change. The association genetics approach potentially offers a powerful way to achieve this, by building upon extensive genomics information and detailed phenotypic analysis. Unfortunately, whole genome association mapping in wild samples requires hundreds of thousands of gene-linked markers, owing to the low levels of linkage disequilibrium in these populations. We propose an experimental strategy to overcome this problem, which exploits the fact that linkage disequilibrium decays at dramatically different rates in different populations. Our approach will use barley as a paradigm for investigating the effectiveness of association mapping in identifying useful gene alleles from the wild. Our second objective is to recruit these new useful gene alleles, into advanced back-cross breeding programs derived from wide crosses between wild barley (H. spontaneum) germplasm and elite cultivars. This will allow us to determine the efficiencies of identification and extraction of useful alleles in barley breeding programs based upon wide crosses. Our third major project objective is to use the huge DNA and marker data set obtained in the project to determine important population genetic parameters for barley.