Fruit tree orchards are faced to multiple pests and diseases which are responsible for significant damages and pesticidesstill remain the most effective means of control. In a context of urgent demand for the reduction of phytosanitary products, alternative and durable solutions must be found. To address these challenges, the selection of resilient trees, i.e. trees that are minimally affected by perturbations or which rapidly return to the state pertained before exposure to these disturbances, seems to be a promising but still misunderstood and under-exploited solution. Thus, a first part of my PhD project aims to define and characterize the phenotypic components of resilience in fruit trees. To do so, two core collections of two stone fruit tree species (apricot and peach) with a high genetic diversity have been deployed and are maintained under low phytosanitary conditions in five contrasted environments. By evaluating the symptoms of the diverse pests and diseases over the years, we might be able to decipher the different strategies and phenotypic manifestations of resilience.