Advances in Ranunculus asiaticus L. genome assembly and annotation based on long-read sequencing technology.

Persian buttercup (Ranunculus asiaticus L.; 2x=2n=16) is a perennial, allogamous species originated in Asia Minor and Mediterranean basin, marketed both as cut flower or potted plant. In 2019, its production counted for 300-350 ha of cultivated area, representing about 0,4% of the total cut flowers turnover, with the highest values in Italy. To meet the increasing market demand and enhance breeding efficiency, a deeper understanding of buttercup genetics and the application of molecular breeding techniques are crucial. The availability of a high-quality genome assembly of the species establishes a reference for exploring the genetic mechanisms of complex traits, thus facilitating molecular breeding of new varieties as well as genomics studies for future application of new breeding techniques. However, due to its wide size, estimated 7,6 Gb, its high level of heterozygosity and the highly presence of repetitive sequences, the assembly of Persian buttercup genome is challenging and remains difficult to fully resolve using short-reads sequencing. Thanks to application of Oxford Nanopore long-reads sequencing, we report on the first version of the R. asiaticus genome assembly and annotation.