Department of Plant Breeding, Swedish University of Agricultural Sciences, P.O. Box 101, 23053 Alnarp, Sweden.
Sejet Plant Breeding, Nørremarksvej 67, 8700 Horsens, Denmark.
Genes (Basel). 2020 Dec 18;11(12):1512. doi: 10.3390/genes11121512.
f. sp. (), the causal agent of barley powdery mildew (PM), is one of the most important barley leaf diseases and is prevalent in most barley growing regions. Infection decreases grain quality and yields on average by 30%. Multi-parent advanced generation inter-cross (MAGIC) populations combine the advantages of bi-parental and association panels and offer the opportunity to incorporate exotic alleles into adapted material. Here, four barley MAGIC populations consisting of six to eight founders were tested for PM resistance in field trials in Denmark. Principle component and STRUCTURE analysis showed the populations were unstructured and genome-wide linkage disequilibrium (LD) decay varied between 14 and 38 Mbp. Genome-wide association studies (GWAS) identified 11 regions associated with PM resistance located on chromosomes 1H, 2H, 3H, 4H, 5H and 7H, of which three regions are putatively novel resistance quantitative trait locus/loci (QTL). For all regions high-confidence candidate genes were identified that are predicted to be involved in pathogen defense. Haplotype analysis of the significant SNPs revealed new allele combinations not present in the founders and associated with high resistance levels.
f. sp. （）是大麦白粉病（PM）的致病因子，是最重要的大麦叶病之一，普遍存在于大多数大麦种植区。感染会使平均谷物产量降低 30%。多亲本高级世代互交（MAGIC）群体结合了双亲和关联群体的优势，并为将外来等位基因纳入适应性材料提供了机会。在这里，四个由六到八个亲本组成的大麦 MAGIC 群体在丹麦的田间试验中进行了 PM 抗性测试。主成分和 STRUCTURE 分析表明，这些群体没有结构，全基因组连锁不平衡（LD）衰减在 14 到 38 Mbp 之间变化。全基因组关联研究（GWAS）鉴定出 11 个与 PM 抗性相关的区域，位于 1H、2H、3H、4H、5H 和 7H 染色体上，其中三个区域是推定的新抗性数量性状位点/基因座（QTL）。所有区域都鉴定出了高可信度的候选基因，这些基因预测参与病原体防御。显著 SNP 的单倍型分析揭示了在亲本中不存在的新等位基因组合，与高抗性水平相关。
