Genome size (GS) varies enormously in plants and has a fundamental impact on genome
divergence and species adaptation. However, the causes and consequences of GS evolution
are still controversial. The Hesperodae clade exhibits genomic features that stand out from other
crucifer supertribes, including several tribes harboring the largest genomes (> 2 Gb), a wide GS
range (30-fold), and low chromosome numbers (n = 6-7). To investigate their evolutionary GS
divergence and elucidate the mechanisms driving GS variation, we propose to combine multiomics
data from eight species representing six of the seven tribes. In this project, we will
compare the genomic landscapes between small vs. large genomes, including the dynamics of
repetitive DNA and patterns of epigenetic modifications. We will investigate the consequences
of GS-associated genomic changes on three-dimensional chromatin organization. We expect
that our results will help uncover the origin of the unusually large genomes in the Hesperodae
clade and improve our understanding of GS evolution in plants.