SOCLE · SOCLE - SOCial SeLEction in cultivated plants

As early shown with social insects, natural selection can maximize group performance by favouring the evolution of altruistic phenotypes. Such social selection has been shown to occur in a wide range of taxon, mainly in animals and microorganisms. Conversely, we have a very poor knowledge of social interactions in plants, mainly because the study of plant-plant interactions has largely remained disconnected from social evolution theory. For example, we don’t know which plant traits have social effects, and we don't know to what extent plant group performance can be affected by social effects. Better understanding social interactions in plants could open new opportunities for plant breeding. Indeed, it has long been suggested that crop yields could be increased by selecting more cooperative varieties. Moreover, advances in animal breeding based on social evolution have already shown convincing results. The aim of this project is thus to better understand social interaction in plants, using crops as a model system. Based on a competition experiment, I will use three approaches: a trait-blind approach, a trait-based approach, and a genomic approach. In the first approach, I will use the indirect genetic effects (IGE) framework to quantify the amount of heritable variation on crop yield that is due to social interactions, and compare it to the non-social heritable variation. With the second approach, I will test the social effects of a set of ecologically and agronomically important traits in order to identify those that contribute most to social interactions. Finally, I will use a genomic approach to look for genomic regions involved in social effects. Conducted in collaboration with plant breeders and leading scientists in the field of social evolution, this multi-disciplinary project will address fundamental research questions related to plant-plant interactions and their evolution, and pave the way for innovative agronomic solutions based on crop cooperation.