Langdon genome assembly and annotation

Durum wheat (<i>Triticum turgidum</i> ssp. <i>durum</i>, 2n = 4x = 28, BBAA) is second most cultivated lineage of wheat after hexaploid common wheat. Langdon is a prominent durum wheat cultivar, highly valued for its crucial role in the development of synthetic hexaploid wheat and its importance in agricultural research. Here, we present a high-quality chromosome-level genome assembly of Langdon using a combination of PacBio HiFi sequencing and Hi-C techniques. The total genome assembly size was 10.47 Gb, with a BUSCO score of 98.8%, QV score of 50.31, and a contig N50 value of 41.18 Mb and the longest contig reached 295.80 Mb. Repetitive elements constituted 88.13% of the assembly, and 68,342 high confidence protein-coding genes were annotated. The high-quality chromosome-level Langdon assembly can serve as a valuable reference for durum wheat, aiding gene research and comparative genomics, and leveraging synthetic hexaploid wheat's genetic resources to advance global wheat improvement.

硬粒小麦（*Triticum turgidum* subsp. *durum*，2n=4x=28，BBAA）是仅次于六倍体普通小麦的第二大栽培小麦谱系。兰登（Langdon）是一款知名的硬粒小麦栽培品种，因其在合成六倍体小麦开发中的关键作用以及在农业研究中的重要价值而广受重视。本研究结合PacBio HiFi测序与Hi-C技术，构建了兰登的高质量染色体级基因组组装序列。该基因组组装总长度为10.47 Gb，通用单拷贝同源基因基准评估（BUSCO）得分为98.8%，测序质量值（QV）为50.31，重叠群（contig）N50为41.18 Mb，最长重叠群长度达295.80 Mb。组装序列中重复序列占比为88.13%，共注释得到68342个高可信度蛋白质编码基因。该高质量兰登染色体级基因组组装可作为硬粒小麦研究的宝贵参考基因组，助力基因研究与比较基因组学分析，并可依托合成六倍体小麦的遗传资源推进全球小麦遗传改良工作。