1. INRA, Agrocampus‐Ouest, Université de Rennes 1, UMR1099 BiO3P (Biology of Organisms and Populations applied to Plant Protection), 65 rue de Saint‐Brieuc, CS 84215, 35 042 Rennes Cedex, France
2. INRA, UMR1099 BiO3P (Biology of Organisms and Populations applied to Plant Protection), Domaine de la Motte, 35653 Le Rheu Cedex, France
3. Laboratoire d’Ecologie Alpine, CNRS UMR 5553, Université Joseph Fourier, 38041 Grenoble Cedex 9, France