Background: Eucalyptus urophylla × Eucalyptus grandis, an economically important forest tree, provides important raw material for energy and reduces damage to native forests. However, the absence of a high-quality E. urophylla × E. grandis reference genome has significantly hindered its evolution and genetic analysis.
Results: We successfully presented a high-quality reference genome of E. urophylla × E. grandis (545.75 Mb; scaffold N50, 51.62 Mb) using a combination of the Illumina, PacBio HiFi, and Hi-C sequencing platforms. A total of 34,502 genes and 58.56% of the repetitive sequences in this genome were annotated. Using genome evolution analyses, we identified a recent whole-genome duplication (WGD) event in E. urophylla × E. grandis. We further found that gene families associated with starch and sucrose metabolism, flavonoid biosynthesis, and plant-pathogen interaction were significantly expanded in E. urophylla × E. grandis. Moreover, comparative genomic and evolutionary analyses showed large structural variations among the different chromosomes of the 34 Eucalyptus accessions, which were divided into six clades.
Conclusions: Overall, our findings provide a valuable resource for expanding our understanding of the E. urophylla × E. grandis genome evolution, genetic improvement, and its comparative biology.
Keywords: Comparative genomics; E. urophylla × E. grandis; Eucalyptus; Genome sequences.
© 2023. The Author(s).