Repeat competition and ecological shifts drive the evolution of the mobilome in Rhynchospora Vahl. (Cyperaceae), the holocentric beaksedges

Genomic changes triggered by polyploidy, chromosomal rearrangements, and/ or environmental stress are among factors that affect the activity of mobile elements, particularly Long Terminal Repeats Retrotransposons (LTR-RTs) and DNA transposons. Because these elements can proliferate and move throughout host genomes, altering the genetic, epigenetic and nucleotypic landscape, they have been recognized as a relevant evolutionary force. Beaksedges (Rhynchospora) stand out for their wide cosmopolitan distribution, high diversity (~400 spp.) and holocentric chromosomes related to high karyotypic diversity and a centromere-specific satDNA Tyba. This makes the genus an interesting model to investigate the interactions between repetitive elements, phylogenetic relationships, and ecological variables.