PDF(Pubmed)
Abstract：
Water availability is undoubtedly one of the most important environmental factors affecting crop production. Drought causes a gradual deprivation of water in the soil from top to deep layers and can occur at diverse stages of plant development. Roots are the first organs that perceive water deficit in soil and their adaptive development contributes to drought adaptation. Domestication has contributed to a bottleneck in genetic diversity. Wild species or landraces represent a pool of genetic diversity that has not been exploited yet in breeding program. In this study, we used a collection of 230 two-row spring barley landraces to detect phenotypic variation in root system plasticity in response to drought and to identify new quantitative trait loci (QTL) involved in root system architecture under diverse growth conditions. For this purpose, young seedlings grown for 21 days in pouches under control and osmotic-stress conditions were phenotyped and genotyped using the barley 50k iSelect SNP array, and genome-wide association studies (GWAS) were conducted using three different GWAS methods (MLM GAPIT, FarmCPU, and BLINK) to detect genotype/phenotype associations. In total, 276 significant marker-trait associations (MTAs; p-value (FDR)< 0.05) were identified for root (14 and 12 traits under osmotic-stress and control conditions, respectively) and for three shoot traits under both conditions. In total, 52 QTL (multi-trait or identified by at least two different GWAS approaches) were investigated to identify genes representing promising candidates with a role in root development and adaptation to drought stress.
摘要：
水供应无疑是影响作物生产的最重要的环境因素之一。干旱导致土壤中的水分从顶层到深层逐渐剥夺，并且可能发生在植物发育的不同阶段。根是感知土壤水分亏缺的第一器官，其适应性发育有助于干旱适应。驯化导致了遗传多样性的瓶颈。野生物种或地方品种代表了尚未在育种计划中利用的遗传多样性。在这项研究中,我们使用了230个两行春季大麦地方品种的集合，以检测响应干旱的根系可塑性的表型变异，并确定在不同生长条件下与根系结构有关的新数量性状基因座（QTL）。为此,使用大麦50kiSelectSNP阵列对在对照和渗透胁迫条件下在袋中生长21天的幼苗进行表型和基因分型，和全基因组关联研究(GWAS)使用三种不同的GWAS方法(MLMGAPIT，FarmCPU,和BLINK）以检测基因型/表型关联。总的来说,对于根（渗透胁迫和控制条件下的14和12个性状，分别）和在两种条件下的三个芽性状。总的来说,研究了52个QTL（多性状或通过至少两种不同的GWAS方法鉴定），以鉴定代表在根发育和适应干旱胁迫中起作用的有希望的候选基因。
