RT Journal Article SR Electronic T1 Genome sequence of Hydrangea macrophylla and its application in analysis of the double flower phenotype JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.06.14.151431 DO 10.1101/2020.06.14.151431 A1 K Nashima A1 K Shirasawa A1 A Ghelfi A1 H Hirakawa A1 S Isobe A1 T Suyama A1 T Wada A1 T Kurokura A1 T Uemachi A1 M Azuma A1 M Akutsu A1 M Kodama A1 Y Nakazawa A1 K Namai YR 2020 UL http://biorxiv.org/content/early/2020/06/15/2020.06.14.151431.abstract AB Owing to its high ornamental value, the double flower phenotype of hydrangea (Hydrangea macrophylla) is one of its most important traits. In this study, genome sequence information was obtained to explore effective DNA markers and the causative genes for double flower production in hydrangea. Single molecule real-time sequencing data followed by a HiC analysis was employed. The resultant haplotype-phased sequences consisted of 3,779 sequences (2.256 Gb in length and N50 of 1.5 Mb), and 18 pseudomolecules comprising 1.08 Gb scaffold sequences along with a high-density SNP genetic linkage map. Using the genome sequence data obtained from two breeding populations, the SNPs linked to double flower loci (Djo and Dsu), were discovered for each breeding population. DNA markers J01 linked to Djo and S01 linked to Dsu were developed, and these could be used successfully to distinguish the recessive double flower allele for each locus respectively. The LEAFY gene was suggested as the causative gene for Dsu, since frameshift was specifically observed in double flower accession with dsu. The genome information obtained in this study will facilitate a wide range of genomic studies on hydrangea in the future.Competing Interest StatementThe authors have declared no competing interest.