2026-09-29 ワシントン大学セントルイス校
<関連情報>
- https://source.washu.edu/2026/09/wild-crabapples-have-genetic-potential-to-improve-domestic-varieties/
- https://onlinelibrary.wiley.com/doi/10.1111/tpj.16433
- https://academic.oup.com/hr/advance-article/doi/10.1093/hr/uhag336/8748472
北米産野生リンゴMalus fuscaのハプロタイプ解析による染色体スケールアセンブリと、火傷病遺伝子 Mfu10 の比較ゲノミクス A haplotype resolved chromosome-scale assembly of North American wild apple Malus fusca and comparative genomics of the fire blight Mfu10 locus
Ben N. Mansfeld, Alan Yocca, Shujun Ou, Alex Harkess, Erik Burchard, Benjamin Gutierrez, Steve van Nocker, Christopher Gottschalk
the Plant Journal Published: 28 August 2023
DOI:https://doi.org/10.1111/tpj.16433

SUMMARY
The Pacific crabapple (Malus fusca) is a wild relative of the commercial apple (Malus × domestica). With a range extending from Alaska to Northern California, M. fusca is extremely hardy and disease resistant. The species represents an untapped genetic resource for the development of new apple cultivars with enhanced stress resistance. However, gene discovery and utilization of M. fusca have been hampered by the lack of genomic resources. Here, we present a high-quality, haplotype-resolved, chromosome-scale genome assembly and annotation for M. fusca. The genome was assembled using high-fidelity long-reads and scaffolded using genetic maps and high-throughput chromatin conformation capture sequencing, resulting in one of the most contiguous apple genomes to date. We annotated the genome using public transcriptomic data from the same species taken from diverse plant structures and developmental stages. Using this assembly, we explored haplotypic structural variation within the genome of M. fusca, identifying thousands of large variants. We further showed high sequence co-linearity with other domesticated and wild Malus species. Finally, we resolve a known quantitative trait locus associated with resistance to fire blight (Erwinia amylovora). Insights gained from the assembly of a reference-quality genome of this hardy wild apple relative will be invaluable as a tool to facilitate DNA-informed introgression breeding.
野生のMalus angustifolia における新たなゲノムリソースと地域適応GWASにより、リンゴの非生物的耐性を高める遺伝子領域が明らかになった New genomic resources and local adaptation GWAS in wild Malus angustifolia reveal genetic regions for enhancing abiotic resiliency in apple
Ben N Mansfeld, Zoë Migicovsky, Jordan Brock, Blake Hewens-Higgins, Erik Burchard, Alan Yocca, Shujun Ou, Lauren Whitt, Anuradha Dhingra, Alex Harkess,…
Horticulture Research Published:31 July 2026
DOI:https://doi.org/10.1093/hr/uhag336
Abstract
Apple (Malus domestica Borkh.) production faces many challenges stemming from abiotic stresses such as extreme temperatures, droughts, and spring frosts. The introduction of resiliency traits from wild Malus relatives that originate from high-stress environments could offer new genetic solutions to a changing climate. Use of wild Malus relatives in breeding is constrained by the lack of genomic resources and base knowledge of genetics associated with abiotic stress. To address this gap, we used a combination of the latest genome sequencing and resequencing approaches to assemble a high-quality reference genome for Malus angustifolia, a native apple to the Southeastern U.S., and resequence its germplasm to enable genome-wide association study identify regions and structural variants associated with abiotic stress resistance. The resulting genome assembly exhibited scaffold N50 of >40 Mb and BUSCO scores >98.7% complete for both haplotype assemblies. We used climate data from the origin of each resequenced sample as a phenotype to identify 242 regions including SNPs and structural variants (deletions, duplications, and inversions) of the genome of M. angustifolia that were significantly associated with abiotic factors such as seasonal precipitation and maximum seasonal temperature. These results will enable identification of resilient M. angustifolia accessions and genetic loci for use in breeding of climate-resilient apples.


