Chrysanthemum Genome Sequencing

Chrysanthemum is a popular and economically important plant in the floricultural industry. Although the development of sequencing technology has enabled the explosive generation of whole genome sequences of diverse plants, chrysanthemum genome is not sequenced yet. Probably, its gigantic genome size and hexaploidy result in the lack or delay of chrysanthemum genome project. Chrysanthemum belongs to the Asteraceae/Compositae family, one of the largest families of angiosperms, shows peculiar inflorescence head structure and pollen presentation and produces diverse secondary metabolite. Since species in Asteraceae exhibit various levels of ploidy from diploid to decaploid, a plant containing the minimum set of chromosome such as diploidy would be the best candidate plant to construct a reference genome sequence for the Asteraceae species. With these backgrounds, we launched a genome sequencing project on chrysanthemum with its wild relative showing diploidy chromosome. To initiate the genome project, we collected diverse chrysanthemum species and characterized their chromosomal structure by cytogenetic analysis. A diploid wild species (C. boreale) was selected to be used as a model plant for chrysanthemum genome project and subjected to the preliminary analysis to examine its basic characteristics in terms of genome itself. For this, we de novo sequenced its genome by using Illumina’s HiSeq platform and performed K-mer frequency analysis. Here, we report our current progress on chrysanthemum genome sequencing project.