Genomic studies on UK flora: cytotype distribution and incidence of polyploidy
Helping to elucidate the existence of hybridization zones
Sorbus minima growing at Craig y Castell in Wales (left) and flow cytometry histogram (right) revealing that this individual is a triploid.
This project has arisen as part of the long-term, ongoing project based in the Jodrell Laboratory focusing on the evolutionary significance of plant genome diversity. Polyploidy, that is the presence of more than two complete chromosome sets per cell, has long been recognized as one of the most important evolutionary forces driving plant speciation. In recent years, techniques including flow cytometry (FCM) have been shown to be powerful tools in elucidating the patterns and dynamics of genome duplication across natural populations, and thus they represent a useful complement to chromosome studies. FCM allows researchers to process large numbers of samples and therefore to perform more accurate frameworks of the geographical incidence of different ploidy levels within plant populations.
Data generated are integrated to gain greater understanding of the principles, processes and phenomena operating at different genomic levels which create and control plant biodiversity. One of the advantages of FCM is that it is not highly destructive, an essential prerequisite for the study of rare and threatened species without compromising their continued survival. Furthermore, the development of novel protocols to estimate DNA ploidy using desiccated plant tissues as an alternative to fresh material reduces the need for the long-term storage of fresh tissue. The use of this technique on current ongoing studies focused on UK taxa (e.g. Sorbus, Tragopogon) is helping to elucidate the existence of hybridization zones and the distribution and coexistence of cytotypes. In turn, this information will contribute to a greater understanding of the species that should be recognized, how they are related to each other and how they should be conserved.
Project partners and collaborators
National Museum of Wales
University of Bristol
University of London, Queen Mary