With populations of threatened and endangered species declining worldwide, efforts are being made to generate high quality genomic records of these species before they are lost forever. Here, we demonstrate that data from single Oxford Nanopore Technologies (ONT) MinION flow cells can, even in the absence of highly accurate short DNA-read polishing, produce high quality de novo plant genome assemblies adequate for downstream analyses, such as synteny and ploidy evaluations, paleodemographic analyses, and phylogenomics. This study focuses on three North American ash tree species in the genus Fraxinus (Oleaceae) that were recently added to the International Union for Conservation of Nature (IUCN) Red List as critically endangered. Our results support a hexaploidy event at the base of the Oleaceae as well as a subsequent whole genome duplication shared by Syringa, Osmanthus, Olea, and Fraxinus. Finally, we demonstrate the use of ONT long-read sequencing data to reveal patterns in demographic history.

随着全球受威胁和濒危物种数量的减少，人们正在努力在这些物种永远消失之前生成高质量的基因组记录。在这里，我们证明来自单个 Oxford Nanopore Technologies (ONT) MinION 流动槽的数据，即使在没有高精度短 DNA 读长精加工的情况下，也可以产生足以进行下游分析（例如同线性和倍性）的高质量从头植物基因组组装。评估、古人口学分析和系统基因组学。本研究重点关注白蜡属（木犀科）中的三种北美白蜡树物种，这些树种最近被列入国际自然保护联盟 (IUCN) 红色名录，列为极度濒危物种。我们的结果支持木犀科基部的六倍体事件以及随后由丁香属、桂花属、木犀属和白蜡属共有的全基因组复制。最后，我们演示了如何使用 ONT 长读长测序数据来揭示人口统计历史模式。