European hazelnut (Corylus avellana L.) is an important tree nut crop. Hazelnut production in North America is currently limited in scalability due to Anisogramma anomala, a fungal pathogen that causes Eastern Filbert Blight (EFB) disease in hazelnut. Successful deployment of EFB resistant cultivars has been limited to the state of Oregon, where the breeding program at Oregon State University (OSU) has released cultivars with a dominant allele at a single resistance locus identified by classical breeding, linkage mapping, and molecular markers. ‘Jefferson’ is resistant to the predominant EFB biotype in Oregon and has been selected by the OSU breeding program as a model for hazelnut genetic and genomic research. Here, we present a near complete, haplotype-resolved chromosome-level hazelnut genome assembly for C. avellana ‘Jefferson’. This new assembly is a significant improvement over a previously published genome draft. Analysis of genomic regions linked to EFB resistance and self-incompatibility confirmed haplotype splitting and identified new gene candidates that are essential for downstream molecular marker development, thereby facilitating breeding efforts.

中文翻译：

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欧洲榛子 (C. avellana cv. Jefferson) 的单倍型解析染色体水平组装和注释提供了对东部榛萎病抗性机制的深入了解

欧洲榛子（Corylus avellana L.）是一种重要的坚果作物。目前，北美榛子生产的规模化受到限制，原因是异形异形菌（Anisogramma anomala），这是一种导致榛子东部榛萎病（EFB）病的真菌病原体。 EFB 抗性品种的成功部署仅限于俄勒冈州，俄勒冈州立大学 (OSU) 的育种计划已在通过经典育种、连锁图谱和分子标记鉴定的单一抗性位点上培育出具有显性等位基因的品种。 “Jefferson”对俄勒冈州主要的 EFB 生物型具有抗性，并已被俄勒冈州立大学育种计划选为榛子遗传和基因组研究的模型。在这里，我们展示了 C. avellana 'Jefferson' 近乎完整的、单倍型解析的染色体水平榛子基因组组装。这个新的组装比之前发布的基因组草图有了重大改进。对与 EFB 抗性和自交不亲和性相关的基因组区域的分析证实了单倍型分裂，并确定了对下游分子标记开发至关重要的新候选基因，从而促进育种工作。