Dep. of Plant Pathology, Univ. of Georgia, Griffin Campus, Griffin, GA, 30223, USA.
Institute of Plant Breeding, Genetics, and Genomics, Univ. of Georgia, Griffin Campus, Griffin, GA, 30223, USA.
Plant Genome. 2022 Sep;15(3):e20222. doi: 10.1002/tpg2.20222. Epub 2022 May 28.
Host resistance is an effective and sustainable approach to manage the negative impact of Fusarium head blight (FHB) on wheat (Triticum aestivum L.) grain yield and quality. The objective of this study was to characterize the phenotypic responses and identify quantitative trait loci (QTL) conditioning different FHB resistance types using a panel of 236 elite soft red winter wheat (SRWW) lines in a genome-wide association study (GWAS). The panel was phenotyped for five FHB and three morphological traits under two field and two greenhouse environments in 2018-2019 and 2019-2020. We identified 160 significant marker-trait associations (MTAs) for FHB traits and 11 MTAs for plant height. Eleven QTL showed major effects and explained >10% phenotypic variation (PV) for FHB resistance. Among these major loci, three QTL were stable and five QTL exhibited a pleiotropic effect. The QTL QFhb-3BL, QFhb-5AS, QFhb-5BL, QFhb-7AS.1, QFhb-7AS.2, and QFhb-7BS are presumed to be novel. Pyramiding multiple resistance alleles from all the major-effect QTL resulted in a significant reduction in FHB incidence, severity, index, deoxynivalenol (DON), and Fusarium-damaged kernel (FDK) by 17, 43, 45, 55, and 25%, respectively. Further validation of these QTL could potentially facilitate successful introgression of these resistance loci in new cultivars for improved FHB resistance in breeding programs.
宿主抗性是管理镰刀菌穗腐病（FHB）对小麦（Triticum aestivum L.）籽粒产量和品质负面影响的有效且可持续的方法。本研究的目的是使用 236 个精英软质红冬小麦（SRWW）品系的图谱进行全基因组关联研究（GWAS），对不同 FHB 抗性类型的表型反应进行特征描述，并鉴定控制不同 FHB 抗性类型的数量性状位点（QTL）。该图谱在 2018-2019 年和 2019-2020 年的两个田间和两个温室环境中对 5 个 FHB 和 3 个形态性状进行了表型鉴定。我们确定了 160 个与 FHB 性状相关的显著标记-性状关联（MTA）和 11 个与株高相关的 MTA。11 个 QTL 表现出主要效应，解释了 FHB 抗性的>10%表型变异（PV）。在这些主要位点中，有 3 个 QTL 稳定，有 5 个 QTL 表现出多效性。假定 QFhb-3BL、QFhb-5AS、QFhb-5BL、QFhb-7AS.1、QFhb-7AS.2 和 QFhb-7BS 是新的 QTL。从所有主要效应 QTL 中聚合多个抗性等位基因可使 FHB 发病率、严重度、指数、脱氧雪腐镰刀菌烯醇（DON）和镰刀菌损伤的籽粒（FDK）分别降低 17%、43%、45%、55%和 25%。对这些 QTL 的进一步验证可能有助于在新的品种中成功导入这些抗性位点，从而在育种计划中提高对 FHB 的抗性。
