Format: ORAL

Jess Picazo-Aragons1, Manuel Narvez1, Ana Brescia-Zapata1, Stefan Dtterl2, Ovidiu Paun3, Anass Terrab1, Francisco Balao1

1 Department of Plant Biology and Ecology, University of Seville, Seville, Spain 2 Department of Environment & Biodiversity, Paris Lodron University Salzburg, Salzburg, Austria 3 Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria

The Dianthus genus, native to Europe and Asia, presents one of the fastest diversification rates ever reported in flowering plants, with a high incidence of polyploidy and over 300 species. Carnation (Dianthus caryophyllus) is one of the most important ornamental flowers, that has been cultivated for centuries, overcoming an extensive domestication process which is largely understudied. Fragrance is an important property of marketable ornamental flowers, but modern carnation cultivars have weak fragrances in contrast to wild carnations. Dianthus broteri is a recently radiated polyploid complex with four cytotypes (2x, 4x, 6x and 12x) endemic to the Iberian Peninsula. This complex, which present a highly diverse scent composition, has been studied as an evolutionary model in the genus. With the objective of understanding the ongoing evolutionary processes of domestication, fragrance divergence and the impact of transposable elements (TEs), we assembled a chromosome-level genome of the diploid Dianthus broteri (876.17 Mb with scaffold N50 53 Mb and 43,817 protein coding genes). We performed comparative genome-wide analyses between the wild carnations D. broteri and D. sylvestris (assembly genome size 443.52 Mb), and cultivated D. caryophyllus Francesco (568.89 Mb) and Aili (584 Mb) varieties. We compared genome structure, gene families gain and losses and TE landscapes. Differences in genome sizes are not the result of the increase in gene content but can be explained due to increase of TEs in D.broteri, with a higher abundance of long terminal repeat-retrotransposons (LTR-RTs). LTRs highly impact the structure, function and evolution of the host genome, and might have an important role in domestication and the divergence between Dianthus species. Furthermore, using transcriptomic data, we have studied MYB transcription factors and terpene synthases to understand the importance of scent emission in wild carnations.