Genome size and polyploids
Variation in genome size arises as a consequence of the amplification/deletion of transposable elements (Lee & Kim 2014) or polyploidy (i.e., whole-genome duplication), the latter often being accompanied by interspecific hybridization (allopolyploidy) (Leitchet al. 2008). Polyploidy usually affects species characteristics in environmental tolerance, adaptation, and plant-microbe interactions (Van de Peer et al. 2021). However, our current study lacks ploidy information for most species and additional studies are needed to determine whether observed effects of genome size in driving β-diversity arise from polyploidization or changes of transposable elements (Shethet al. 2020).