Sertse Demissew, Haile Jemanesh K, Sari Ehsan, Klymiuk Valentyna, N'Diaye Amidou, Pozniak Curtis J, Cloutier Sylvie, Kagale Sateesh
Aquatic and Crop Resource Development, National Research Council Canada, Saskatoon, Saskatchewan, Canada.
Department of Plant Science, Faculty of Agricultural and Food Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.
Plant Genome. 2025 Mar;18(1):e20410. doi: 10.1002/tpg2.20410. Epub 2023 Nov 16.
Tetraploid wheats (Triticum turgidum L.), including durum wheat (T. turgidum ssp. durum (Desf.) Husn.), are important crops with high nutritional and cultural values. However, their production is constrained by sensitivity to environmental conditions. In search of adaptive genetic signatures tracing historical selection and hybridization events, we performed genome scans on two datasets: (1) Durum Global Diversity Panel comprising a total of 442 tetraploid wheat and wild progenitor accessions including durum landraces (n = 286), domesticated emmer (T. turgidum ssp. dicoccum (Schrank) Thell.; n = 103) and wild emmer (T. turgidum ssp. dicoccoides (Korn. ex Asch. & Graebn.) Thell.; n = 53) wheats genotyped using the 90K single nucleotide polymorphism (SNP) array, and (2) a second dataset comprising a total 121 accessions of nine T. turgidum subspecies including wild emmer genotyped with >100 M SNPs from whole-genome resequencing. The genome scan on the first dataset detected six outlier loci on chromosomes 1A, 1B, 3A (n = 2), 6A, and 7A. These loci harbored important genes for adaptation to abiotic stresses, phenological responses, such as seed dormancy, circadian clock, flowering time, and key yield-related traits, including pleiotropic genes, such as HAT1, KUODA1, CBL1, and ZFN1. The scan on the second dataset captured a highly differentiated region on chromosome 2B that shows significant differentiation between two groups: one group consists of Georgian (T. turgidum ssp. paleocolchicum A. Love & D. Love) and Persian (T. turgidum ssp. carthlicum (Nevski) A. Love & D. Love) wheat accessions, while the other group comprises all the remaining tetraploids including wild emmer. This is consistent with a previously reported introgression in this genomic region from T. timopheevii Zhuk. which naturally cohabit in the Georgian and neighboring areas. This region harbored several adaptive genes, including the thermomorphogenesis gene PIF4, which confers temperature-resilient disease resistance and regulates other biological processes. Genome scans can be used to fast-track germplasm housed in gene banks and in situ; which helps to identify environmentally resilient accessions for breeding and/or to prioritize them for conservation.
四倍体小麦（普通小麦），包括硬粒小麦（普通小麦硬粒亚种），是具有高营养价值和文化价值的重要作物。然而，它们的产量受到对环境条件敏感性的限制。为了寻找追踪历史选择和杂交事件的适应性遗传特征，我们对两个数据集进行了全基因组扫描：（1）硬粒小麦全球多样性面板，共包括442份四倍体小麦和野生祖先种质，其中有硬粒地方品种（n = 286）、驯化二粒小麦（普通小麦二粒亚种；n = 103）和野生二粒小麦（普通小麦野生二粒亚种；n = 53），使用90K单核苷酸多态性（SNP）阵列进行基因分型；（2）第二个数据集，共包括9个普通小麦亚种的121份种质，其中野生二粒小麦通过全基因组重测序获得超过1亿个SNP进行基因分型。对第一个数据集的全基因组扫描在1A、1B、3A（n = 2）、6A和7A染色体上检测到6个异常位点。这些位点包含了适应非生物胁迫、物候反应（如种子休眠、生物钟、开花时间）以及关键产量相关性状的重要基因，包括多效性基因，如HAT1、KUODA1、CBL1和ZFN1。对第二个数据集的扫描在2B染色体上捕获到一个高度分化的区域，该区域在两组之间表现出显著差异：一组由格鲁吉亚小麦（普通小麦古科尔奇亚种）和波斯小麦（普通小麦卡尔西卡亚种）种质组成，而另一组包括所有其余的四倍体，包括野生二粒小麦。这与之前报道的该基因组区域从提莫菲维小麦渗入的情况一致，提莫菲维小麦自然生长在格鲁吉亚及周边地区。该区域包含几个适应性基因，包括赋予温度弹性抗病性并调节其他生物学过程的热形态建成基因PIF4。全基因组扫描可用于快速筛选基因库和原位保存的种质；这有助于识别具有环境适应性的种质用于育种和/或将它们列为优先保护对象。
