Drought seriously curtails growth, physiology and productivity in rapeseed (Brassica napus). Although drought tolerance is a complex trait, efficient phenotyping and genotyping has led to the identification of novel marker-trait associations underlying drought tolerance. A diverse panel of 228 Brassica accessions was phenotyped under normal (without stress) and water-stress conditions, simulated by polyethylene glycol (PEG-6000) (15% PEG stress) at the seedling stage; stress tolerance index (STI) and stress susceptibility index (SSI) values were acquired. Genome-wide association studies (GWAS) using 201 817 high quality SNPs identified 314 marker-trait associations strongly linked with drought indices and distributed across all nineteen chromosomes in both the A and C genomes. None of these quantitative trait loci (QTL) had been previously identified by other studies. We identified 85 genes underlying these QTL (most within 100 kb of associated SNPs) which were orthologous to Arabidopsis genes known to be associated with drought tolerance. Our study provides a novel resource for breeding drought-tolerant Brassica crops.

干旱严重降低了油菜籽（甘蓝型油菜）的生长，生理和生产力。尽管耐旱性是一个复杂的特征，有效的表型和基因分型已导致鉴定出抗旱性的新型标记-性状关联。228芸苔属植物的多样化面板在正常（无胁迫）和水分胁迫条件下，对种质进行表型分析，在苗期用聚乙二醇（PEG-6000）（15％PEG胁迫）模拟。获得应力耐受指数（STI）和应力敏感性指数（SSI）值。使用201 817个高质量SNP进行的全基因组关联研究（GWAS）确定了314个与干旱指数密切相关的标记-性状关联，并分布在A和C基因组的所有19个染色体上。这些定量性状基因座（QTL）以前没有被其他研究鉴定。我们确定了这些QTL的85个基因（大多数位于相关SNP的100 kb之内），这些基因与已知与干旱耐受性相关的拟南芥基因同源。本研究为抗旱育种提供了新的资源。芸苔属作物。