Diploid Mercurialis annua from Central and Western Europe was the result of long-range colonization from ancestral populations in the eastern Mediterranean basin. Colonization-front populations are expected to have reduced fitness due to sequential bottlenecks during colonization. To test up to which point fitness in these populations can be increased by heterosis, polycrosses between different colonization-front populations in France, Spain and UK and between them and ancestral populations in Greece and Turkey are currently being performed at the UNIL greenhouses. This seed material will be used in a quantitative genetic experiment to be installed in Switzerland (under Atlantic/continental climate) and Spain (under Mediterranean climate) in spring 2015.
Crossing scheme and open “boxes” used for crosses at UNIL