Li Jie, Yao Xiaohua, Yao Youhua, An Likun, Feng Zongyun, Wu Kunlun
College of Agronomy Sichuan Agricultural University, Chengdu, China.
Academy of Agricultural and Forestry Sciences, Qinghai University, Xining, China.
Front Plant Sci. 2022 Jun 23;13:924892. doi: 10.3389/fpls.2022.924892. eCollection 2022.
Drought stress is one of the main factors restricting hulless barley ( L. var. Hook. f.) yield. Genome-wide association study was performed using 269 lines of hulless barley to identify single-nucleotide polymorphism (SNP) markers associated with drought-resistance traits. The plants were cultured under either normal or drought conditions, and various quantitative traits including shoot fresh weight, shoot dry weight, root fresh weight, root dry weight, leaf fresh weight, leaf saturated fresh weight, leaf dry weight, ratio of root and shoot fresh weight, ratio of root and shoot dry weight, shoot water loss rate, root water loss rate, leaf water content and leaf relative water content, and field phenotypes including main spike length, grain number per plant, grain weight per plant, thousand grain weight (TGW), main spike number, plant height, and effective spike number of plants were collected. After genotyping the plants, a total of 8,936,130 highly consistent population SNP markers were obtained with integrity > 0.5 and minor allele frequency > 0.05. Eight candidate genes potentially contributed to the hulless barley drought resistance were obtained at loci near significant SNPs. For example, , and genes for effective spike number of plants, gene for main spike number (MEN), gene for main spike length, gene for root and shoot dry weight (RSWD), and and genes for TGW. The SNPs and candidate genes identified in this study will be useful in hulless barley breeding under drought resistance.
干旱胁迫是限制青稞（L. var. Hook. f.）产量的主要因素之一。利用269份青稞材料进行全基因组关联研究，以鉴定与抗旱性状相关的单核苷酸多态性（SNP）标记。将植株分别在正常或干旱条件下培养，并收集包括地上部鲜重、地上部干重、根鲜重、根干重、叶鲜重、叶饱和鲜重、叶干重、根冠鲜重比、根冠干重比、地上部失水率、根失水率、叶含水量和叶相对含水量等各种数量性状，以及包括主穗长、单株粒数、单株粒重、千粒重（TGW）、主穗数、株高和有效穗数等田间表型。对植株进行基因分型后，共获得8936130个高度一致的群体SNP标记，完整性>0.5，次要等位基因频率>0.05。在显著SNP附近的位点获得了8个可能对青稞抗旱性有贡献的候选基因。例如，与植株有效穗数相关的、和基因，与主穗数（MEN）相关的基因，与主穗长相关的基因，与根冠干重（RSWD）相关的基因，以及与TGW相关的和基因。本研究中鉴定出的SNP和候选基因将有助于青稞的抗旱育种。
