ADAPTHESE (2019 - 2022)

Disease resistance is a major objective in plant breeding. The main limitation of using resistant varieties is the ability of pathogens to adapt. While major resistance genes are often rapidly ineffective due to pathogen adaptation, partial resistance and tolerance exert a lower selection pressure on pathogens and are therefore assumed to be more durable. However, little information is presently available on the ability of pathogens to adapt to partial resistance and tolerance. The objective of the thesis is therefore to characterize the durability potential of partial resistance and tolerance genes available in genetic resources of pepper (Capsicum annuum L.) by experimental evolution carried out on two viruses (Potato virus Y and Cucumber mosaic virus) and an oomycete (Phytophthora capsici), responsible for major diseases in pepper.