Annals of Botany

Spatio-temporal dynamics of diploid – polyploid contact zones in an annual herb

Hybrid zones, or zones of genetic admixture of different intraspecific cytotypes, provide clues to evolutionary transitions and the mechanisms of polyploid speciation. Čertner et al. present insights into the spatio-temporal dynamics of diploid – polyploid contact zones.

A theoretical overview of crosses involving reduced (dashed arrows) and unreduced (solid arrows) gametes of diploid (red with black stroke) and tetraploid (blue with black stroke) parents and cytotypes of the resulting offspring
A theoretical overview of crosses involving reduced (dashed arrows) and unreduced (solid arrows) gametes of diploid (red with black stroke) and tetraploid (blue with black stroke) parents and cytotypes of the resulting offspring. Numbers refer to relative genome sizes of particular gametes (regular font) and cytotypes (bold font). Notice that some cytotypes have more than one way of origin and these can be easily distinguished based on relative genome size in Tripleurospermum inodorum. For simplicity, other possible crosses involving derived cytotypes are not shown

A combination of flow cytometry and large-scale field sampling enables comparison of cytotype diversity across spatial and temporal scales and ontogenetic stages in the common annual herb Tripleurospermum inodorum (Asteraceae). Temporal changes in ploidy composition were detected at within-population and landscape scales. Widespread coexistence of diploids and tetraploids in Central Europe enables inter-ploidy mating and leads to striking variation in DNA content among offspring. The study highlights the dynamic nature of contact zones and their high potential to generate cytogenetic novelty.

Polyploidy Special Issue Cover This paper is part of the Annals of Botany Special Issue on Polyploidy in Ecology and Evolution. It will be free access until October 2017, then available only to subscribers until August 2018 when it will be free access again.

Reference

Čertner, M., Fenclová, E., Kúr, P., Kolář, F., Koutecký, P., Krahulcová, A., & Suda, J. (2017). Evolutionary dynamics of mixed-ploidy populations in an annual herb: dispersal, local persistence and recurrent origins of polyploids. Annals of Botany, 120(2), 303–315. https://doi.org/10.1093/aob/mcx032

About the author

Annals of Botany Office

The Annals of Botany Office is based at the University of Oxford.

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