摘要
The large genomes of ferns have long deterred genome sequencing efforts. To date, only two heterosporous ferns with remarkably small genomes, Azolla filiculoides and Salvinia cucullata, have been sequenced. However, as sequencing technologies continue to improve and become more affordable, generating high-quality, "normal-sized" fern genomes is within reach. Here we provide new genome size data and discuss candidates for whole genome sequencing. In particular, we identified 18 species representing major branches in the fern phylogeny that are worth pursuing. We also review the current sequencing technologies and offer our opinions on the best sequencing approach for these fern species.