Fern Genomes on the Horizon

Ferns are the final frontier in plant comparative genomics. Although ferns are known to have notoriously large genome sizes (average 1C>10 Gb), our ongoing work has identified some small-genome species. As a community effort, we have assembled and annotated two complete heterosporous fern genomes: Salvinia cucullata and Azolla filiculoides, and here I will highlight some of our key findings. I will also present our progress on three additional fern genomes of Pilularia, Dipteris, and Adiantum, which together with Ceratopteris, will provide a broader picture of fern genome evolution.