Pan-genome analyses of eleven Fraxinus species reveal salt-tolerant associated structural variations

The study initially sequenced and assembled 11 high-quality genome assemblies for Fraxinus species, representing four of the six Fraxinus taxa and around 48% of ash species. A graph-based pan-genome architecture of Fraxinus was built using genome assemblies, and genomic PAVs across different species were identified. Then, using an inter-species cross F1 population of F. velutina (salt-tolerant) between F. pennsylvanica (salt-sensitive), a salt tolerance PAV-based quantitative trait loci (QTL) mapping was done to determine putative PAV-QTLs associated with Fraxinus salt tolerance. Finally, potential PAV-QTL genes were identified and experimentally validated to function in Fraxinus responding to salt stress. The data presented here can be helpful genomics resources for Fraxinus salt resistance breeding applications and the research community.