Abstract：
The root tissues play important roles in water and nutrient acquisition, environmental adaptation, and plant development. In this study, a diversity panel of 388 wheat accessions was collected to investigate nine root system architecture (RSA) traits at the three-leaf stage under two growing environments: outdoor pot culture (OPC) and indoor pot culture (IPC). Phenotypic analysis revealed that root development was faster under OPC than that under IPC and a significant correlation was observed between the nine RSA traits. The 660K single-nucleotide polymorphism (SNP) chip was used for a genome-wide association study (GWAS). Significant SNPs with a threshold of -log10 (p-value) ≥ 4 were considered. Thus, 36 quantitative trait loci (QTLs), including 13 QTL clusters that were associated with more than one trait, were detected, and 31 QTLs were first identified. The QTL clusters on chromosomes 3D and 5B were associated with four and five RSA traits, respectively. Two candidate genes, TraesCS2A01G516200 and TraesCS7B01G036900, were found to be associated with more than one RSA trait using haplotype analysis, and preferentially expressed in the root tissues. These favourable alleles for RSA traits identified in this study may be useful to optimise the root system in wheat.
摘要：
根组织在水分和养分获取中起着重要作用，环境适应,和植物发育。在这项研究中,收集了388个小麦种质的多样性小组，以研究在两种生长环境下三叶阶段的9个根系结构（RSA）性状：户外盆栽（OPC）和室内盆栽（IPC）。表型分析表明，OPC下的根系发育比IPC下的根系发育更快，并且在9个RSA性状之间观察到显着的相关性。660K单核苷酸多态性（SNP）芯片用于全基因组关联研究（GWAS）。考虑阈值为-log10(p值)≥4的显著SNP。因此，36个数量性状位点（QTLs），包括13个与一个以上性状相关的QTL簇，被检测到，并首次确定了31个QTL。3D和5B染色体上的QTL簇与四个和五个RSA性状相关，分别。两个候选基因,使用单倍型分析，发现TraesCS2A01G516200和TraesCS7B01G036900与一个以上的RSA性状相关，并优先在根组织中表达。在这项研究中确定的RSA性状的这些有利等位基因可能有助于优化小麦的根系。
