Sonia Demal

Master in Biology

Research interests

Plants have to defend themselves against herbivory and be able to sustain damage while growing, which is called a growth-defense tradeoff. At high altitude, resources are scarce and abiotic conditions are harsh, making it costly for plants to produce biomass. There are two different parameters driving plant defenses : herbivore pressure and resource availability. Herbivore pressure is higher at low altitude so plants are expected to defend themselves more at low than at high altitude. On the contrary, as resources are less scarce at low altitude, they are expected to be less defended than plants living at higher altitudes as it is easier to produce biomass to compensate the loss due to herbivory.

Cardamine sp. are wild plants from the Brassicaceae family and are found from the montane zone to the alpine zone, covering a large altitudinal gradient. They produce specific defense compounds against generalist herbivores called glucosinolates. Pieris sp. are specialist herbivores of the plants of this family and are able to sequester those compounds, allowing them to eat those plants.

My project is based on several Cardamine species and on the impact of herbivory by one of the member of the Pieris family (Pieris rapae). I study their resistance to herbivory along an altitudinal gradient, meaning that I measure their physical and chemical defenses, as well as their tolerance to herbivory, meaning their ability to reproduce biomass and sustain damage. The aim of this project is to determine the adaptative and defensive differences between those species of Cardamine.

Main topics

  • Altitudinal gradient
  • Plant defenses
  • Glucosinolates
  • Herbivory tolerance

Sonia Demal



+41 32 718 23 18