Abstract:
The laurel family within the Magnoliids has attracted attentions owing to its scents, variable
inflorescences, and controversial phylogenetic position. Here, we present a chromosomelevel
assembly of the Litsea cubeba genome, together with low-coverage genomic and
transcriptomic data for many other Lauraceae. Phylogenomic analyses show phylogenetic
discordance at the position of Magnoliids, suggesting incomplete lineage sorting during the
divergence of monocots, eudicots, and Magnoliids. An ancient whole-genome duplication
(WGD) event occurred just before the divergence of Laurales and Magnoliales; subsequently,
independent WGDs occurred almost simultaneously in the three Lauralean lineages. The
phylogenetic relationships within Lauraceae correspond to the divergence of inflorescences,
as evidenced by the phylogeny of FUWA, a conserved gene involved in determining panicle
architecture in Lauraceae. Monoterpene synthases responsible for production of specific
volatile compounds in Lauraceae are functionally verified. Our work sheds light on the evolution
of the Lauraceae, the genetic basis for floral evolution and specific scents.