A chromosome-scale genome assembly of the Mongolian oak (Quercus mongolica)

Mongolian oak (Quercus mongolica Fisch.) is an ecologically and economically important white oak species native to and widespread in the temperate zone of East Asia. Here, we present a chromosome-scale reference genome assembly of Q. mongolica, a representative white oak species, by combining Illumina and PacBio data with Hi-C mapping technologies that is the first reference genome created for an Asian oak. Our results showed that the PacBio draft genome size was 809.84 Mb, with a BUSCO complete gene percentage of 92.71%. Hi-C scaffolding anchored 774.59 Mb contigs (95.65% of draft assembly) onto 12 pseudochromosomes. The contig N50 and scaffold N50 were 2.64 Mb and 66.74 Mb, respectively. We further annotated 36,553 protein-coding genes and 435.34 Mb (53.75% of the genome) repetitive sequences. The non-coding RNAs were identified, including 129 miRNAs, 768 tRNAs, 4,896 rRNAs, and 371 snRNAs. This pioneering Asian oak genome resource represents an important supplement to the oak genomics community and will improve our understanding of Asian white oak biology and evolution.