Didier Tharreau,Deputy Head of To CIRAD. His work is to assess the risk of emergence and to define new strategies for durable control, our objective is to understand how populations of plant-pathogenic fungi develop and adapt. By theoretical and experimental approaches in epidemiology and evolutionary biology, we address the following research topics:Origin of emerging diseases; Importance of various evolutionary forces in the adaptation;Genetic constraints on traits involved in adaptation;Epidemilogical and adaptative dynamics of fungi in agroecosystems.