De novo whole-genome assembly in an interspecific hybrid table grape, 'Shine Muscat'

The first genome sequence of an interspecific grape hybrid (Vitis labruscana × Vitis vinifera), 'Shine Muscat', an elite table grape cultivar bred in Japan, is presented. The resultant genome assemblies included two types of sequences: a haplotype-phased sequence of the highly heterozygous genomes and an unphased sequence representing a 'pseudo-haploid' genome. The unphased sequences, assembled to the chromosome level with Hi-C reads, spanned 488.97 Mb in length, 99.1% of the estimated genome size, with 4,595 scaffold sequences and a 23.9-Mb N50 length. The phased sequences had 15,650 scaffolds spanning 1.0 Gb and a 4.2-Mb N50 length. 32,827 high-confidence genes were predicted on the unphased genomes. Clustering analysis of the 'Shine Muscat' gene sequences with three other Vitis species and Arabidopsis indicated that 11,279 orthologous gene clusters were common to Vitis spp. and Arabidopsis, 4,385 were Vitis specific, and 234 were 'Shine Muscat' specific. Whole-genome resequencing was also performed for the parental lines of 'Shine Muscat', Akitsu-21 and 'Hakunan', and parental-specific copy number variations were identified. The obtained genome resources provide new insights that could assist in cultivation and breeding strategies to produce high-quality table grapes.