Université de Fribourg

Increased seed survival and seedling emergence in a polyploid plant invader

Hahn, Min A. ; Lanz, Tabea ; Fasel, Dominique ; Müller-Schärer, Heinz

In: American Journal of Botany, 2013, vol. 100, no. 8, p. 1555–1561

Premise of the study: Because seeds have essential functions in the life cycle of plants, even subtle changes in their characteristics may have important demographic consequences. In this study, we examined whether potential changes in seed characteristics as a result of polyploidy or postintroduction evolution may have contributed to the invasion of Centaurea stoebe (Asteraceae). This plant...

Université de Fribourg

Effects of soil fungi, disturbance and propagule pressure on exotic plant recruitment and establishment at home and abroad

Maron, John L. ; Waller, Lauren P. ; Hahn, Min A. ; Diaconu, Alecu ; Pal, Robert W. ; Müller-Schärer, Heinz ; Klironomos, John N. ; Callaway, Ragan M.

In: Journal of Ecology, 2013, p. -

Biogeographic experiments that test how multiple interacting factors influence exotic plant abundance in their home and recipient communities are remarkably rare. We examined the effects of soil fungi, disturbance and propagule pressure on seed germination, seedling recruitment and adult plant establishment of the invasive Centaurea stoebe in its native European and non-native North American...

Université de Fribourg

Cytotype differences modulate eco-geographical differentiation in the widespread plant Centaurea stoebe

Hahn, Min A. ; Müller-Schärer, Heinz

In: Ecology, 2013, vol. 94, no. 5, p. 1005–1014

The evolution of optimal life history strategies is central for the fitness of organisms in a given environment. Besides divergent selection, other factors may determine regional patterns of differentiation and contribute to life history evolution. In a common-garden environment over three years, we examined life history differentiation across different eco-geographical regions and effects of a...

Université de Fribourg

Increased phenotypic plasticity to climate may have boosted the invasion success of polyploid Centaurea stoebe

Hahn, Min A. ; Kleunen, Mark van ; Müller-Schärer, Heinz

In: PLoS ONE, 2012, vol. 7, no. 11, p. e50284

Phenotypic plasticity may allow organisms to cope with altered environmental conditions as e.g. after the introduction into a new range. In particular polyploid organisms, containing more than two sets of chromosomes, may show high levels of plasticity, which could in turn increase their environmental tolerance and invasiveness. Here, we studied the role of phenotypic plasticity in the invasion...