Fusarium head blight (FHB) is the predominant disease in oat in Norway caused by the fungus Fusarium graminearum. It causes yield loss, reduced seed quality, reduced germination ability and accumulation of deoxynivalenol (DON). The FHB resistance is quantitative, and most genes have small effect. Markers with verified effect in the breeding program could further enhance the resistance breeding. This study aims to use a large and diverse population of 541 lines to identify quantitative trait loci (QTL) associated to FHB resistance in a genome-wide association study (GWAS) and verify their effect in independent breeding material. The material has been tested in six environments over three years and two locations in spawn inoculated and mist irrigated disease trials. The traits tested were germination ability and DON accumulation. A total of 15 significant QTL-regions were detected across 12 different linkage groups. Haplotypes for each region was constructed and the effect of the alleles in each environment was calculated, which identified the most likely resistant and susceptible alleles. Five QTL-regions were validated showing consistent effect in the GWAS population and the breeding material. Stacking of the resistant alleles of these regions from zero to five showed significant decrease in DON values and increased germination ability. The haplotype information of a set of historical and modern Nordic varieties were analysed, and the results could be used to select parents for future crossings. The validated haplotypes from this study can be used either to do marker assisted selection (MAS) or improve genomic prediction models in breeding programs.

中文翻译：

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春燕麦（Avena sativa L.）抗禾谷镰刀菌相关单倍型的鉴定

赤霉病（FHB）是挪威燕麦的主要病害，由真菌禾谷镰刀菌引起。它会导致产量损失、种子质量下降、发芽能力下降和脱氧雪腐镰刀菌烯醇 (DON) 积累。 FHB抗性是定量的，大多数基因影响很小。在育种计划中经过验证效果的标记可以进一步增强抗性育种。本研究旨在利用 541 个品系的庞大且多样化的群体，在全基因组关联研究 (GWAS) 中鉴定与 FHB 抗性相关的数量性状位点 (QTL)，并验证其在独立育种材料中的效果。该材料已在三年内的六个环境和两个地点进行了菌种接种和雾灌疾病试验的测试。测试的性状为发芽能力和DON积累。在 12 个不同的连锁群中总共检测到 15 个显着的 QTL 区域。构建了每个区域的单倍型，并计算了每个环境中等位基因的影响，从而确定了最可能的耐药和易感等位基因。五个 QTL 区域经过验证，在 GWAS 群体和育种材料中显示出一致的效果。这些区域的抗性等位基因从 0 到 5 的叠加显示 DON 值显着降低，发芽能力增加。对一组历史和现代北欧品种的单倍型信息进行了分析，结果可用于选择未来杂交的亲本。本研究中经过验证的单倍型可用于进行标记辅助选择 (MAS) 或改进育种计划中的基因组预测模型。