Université de Fribourg

Biological invasion of oxeye daisy (Leucanthemum vulgare) in North America: Pre-adaptation, post-introduction evolution, or both?

Stutz, Sonja ; Mráz, Patrik ; Hinz, Hariet L. ; Müller-Schärer, Heinz ; Schaffner, Urs

In: PLOS ONE, 2018, vol. 13, no. 1, p. e0190705

Species may become invasive after introduction to a new range because phenotypic traits pre-adapt them to spread and become dominant. In addition, adaptation to novel selection pressures in the introduced range may further increase their potential to become invasive. The diploid Leucanthemum vulgare and the tetraploid L. ircutianum are native to Eurasia and have been introduced to North...

Université de Fribourg

Ploidy level in the genus Leucanthemum correlates with resistance to a specialist herbivore

Stutz, Sonja ; Hinz, Hariet L. ; Konowalik, Kamil ; Müller-Schärer, Heinz ; Oberprieler, Christoph ; Schaffner, Urs

In: Ecosphere, 2016, vol. 7, no. 9, p. -

Polyploidy is considered to be a major source of genetic diversity in plants. Genome duplication has been shown repeatedly to be associated with changes in biotic interactions, but little is known about whether species traits such as herbivore resistance consistently change with increasing ploidy level among closely related plant species. We tested whether larval survival and performance of...

Université de Fribourg

Can enemy release explain the invasion success of the diploid Leucanthemum vulgare in North America?

Stutz, Sonja ; Štajerová, Kateřina ; Hinz, Hariet L. ; Müller-Schärer, Heinz ; Schaffner, Urs

In: Biological Invasions, 2016, p. 1–15

Enemy release is a commonly accepted mechanism to explain plant invasions. Both the diploid Leucanthemum vulgare and the morphologically very similar tetraploid Leucanthemum ircutianum have been introduced into North America. To verify which species is more prevalent in North America we sampled 98 Leucanthemum populations and determined their ploidy level. Although polyploidy has repeatedly...

Université de Fribourg

Two shoot-Miners, Ceutorhynchus alliariae and Ceutorhynchus roberti, sharing the same fundamental niche on garlic mustard

Gerber, Esther ; Hinz, Hariet L. ; Blossey, Bernd ; Bacher, Sven

In: Environmental Entomology, 2012, vol. 41, no. 5, p. 1086-1096

A combination of observational and experimental methods, in both the laboratory and field, were used to assess niche partitioning between Ceutorhynchus alliariae Brisout and C. roberti Gyllenhal (Coleoptera: Curculionidae), two coexisting shoot-boring weevils on garlic mustard, Alliaria petiolata (M. Bieb.) Cavara and Grande (Brassicaceae). We compared their morphology, oviposition behavior,...