Department of Evolutionary Biology, Faculty of Natural Sciences, Institute of Evolution, University of Haifa, Mt. Carmel, Haifa, Israel.
Mol Ecol. 2012 Mar;21(5):1115-29. doi: 10.1111/j.1365-294X.2011.05434.x. Epub 2012 Jan 18.
The domestication of plants frequently results in a high level of genetic differentiation between domesticated plants and their wild progenitors. This process is counteracted by gene flow between wild and domesticated plants because they are usually able to inter-mate and to exchange genes. We investigated the extent of gene flow between wild barley Hordeum spontaneum and cultivated barley Hordeum vulgare, and its effect on population structure in wild barley by analysing a collection of 896 wild barley accessions (Barley1K) from Israel and all available Israeli H. vulgare accessions from the Israeli gene bank. We compared the performance of simple sequence repeats (SSR) and single nucleotide polymorphisms (SNP) marker data genotyped over a core collection in estimating population parameters. Estimates of gene flow rates with SSR markers indicated a high level of introgression from cultivated barley into wild barley. After removing accessions from the wild barley sample that were recently admixed with cultivated barley, the inference of population structure improved significantly. Both SSR and SNP markers showed that the genetic population structure of wild barley in Israel corresponds to the three major ecogeographic regions: the coast, the Mediterranean north and the deserts in the Jordan valley and the South. Gene flow rates were estimated to be higher from north to south than in the opposite direction. As has been observed in other crop species, there is a significant exchange of alleles between the wild species and domesticated varieties that needs to be accounted for in the population genetic analysis of domestication.
植物的驯化常常导致驯化植物与其野生祖先之间存在高度的遗传分化。然而，由于野生和驯化植物之间通常能够相互交配和交换基因，基因流会抵消这种分化。我们通过分析来自以色列的 896 个野生大麦（Barley1K）和以色列基因库中所有可用的以色列栽培大麦（Hordeum vulgare），调查了野生大麦（Hordeum spontaneum）和栽培大麦之间的基因流程度及其对野生大麦种群结构的影响。我们比较了在核心样本中对简单序列重复（SSR）和单核苷酸多态性（SNP）标记数据进行基因型分析的表现，以估计种群参数。SSR 标记估计的基因流速率表明，从栽培大麦到野生大麦的基因渗入程度很高。在从野生大麦样本中去除最近与栽培大麦混合的个体后，种群结构的推断显著改善。SSR 和 SNP 标记都表明，以色列野生大麦的遗传种群结构与三个主要的生态地理区域相对应：沿海地区、地中海北部、约旦河谷和南部的沙漠地区。从北到南的基因流速率估计高于相反方向的基因流速率。与其他作物物种一样，野生种和驯化品种之间存在显著的等位基因交换，这在驯化的种群遗传分析中需要加以考虑。
