Chromosome-level phased genome assembly of the Argan tree Sideroxylon spinosum L.

Argan (Sideroxylon spinosum L. previously known as Argania spinosa) is an endemic tree of Morocco, primarily used for seed oil extraction. Increasing interest in its biology and in genes relevant for oil quality and stress resistance demands for high-quality models of its genome and transcriptome. We integrated sequencing data from PacBio HiFi long-reads and Illumina Hi-C to generate independently assembled phased genome models for both parental haplotigs with lengths of 636Mb and 655 Mb, respectively, and with a BUSCO completeness score of >97.8%. Both haplotigs consist of 11 independently assembled fully resolved telomere-to-telomere chromosomes, similar to other species of the Sapotaceae (n = 10-13), and they both contain approximately [~]60% of highly repetitive regions. Comparative analysis with other Sapotaceous genomes suggests overall chromosome conservation, with repeat expansion and chromosome fusion for the two largest chromosomes (chr1, chr2). We also independently assembled the chloroplast genome. This high-quality genome assembly provides a valuable resource for advancing future research on argan biology, its genetic diversity, and traits relevant for fitness and oil production.