Large scale ploidy surveys using flow cytometry have become an essential tool to study plant genome dynamics and to get insights into the mechanisms and genetic barriers framing ploidy diversity. Pellicer et al. study Sorbus ploidy diversity in southern Wales and south-west England, revealing the presence of ploidy levels ranging from diploids to pentaploids, the latter occurring at a very low frequency. The noteworthy coexistence of several cytotypes in Sorbus populations is probably facilitated by the overlapping distribution of many of the species studied, which may also explain the high incidence of potential hybrid apomictic polyploids.
