Apports de la modélisation pour analyser les interactions entre plantes et définir les composantes des prairies multi-espèces – l’exemple de Virtual GrassLand

Contributions of modelling to analyzing plant-plant interactions and defining the components of multi-species grasslands – the example of Virtual GrassLand

Faced with the challenges of climate change and the need to reduce inputs, multi-species grasslands appear to be a major lever for strengthening the resilience and sustainability of forage systems. Their agronomic success is recognized, but the best way to adapt them to these challenges remains to be defined. Individual-based models, such as Virtual GrassLand, can simulate plant-plant interactions and grassland community dynamics, providing a virtual laboratory for testing species compositions, traits of interest, and cultural practices (e.g., variety mixtures). For example, they have been used to show through simulation that the objectives of overproduction and stability over time in grass-legume mixtures are achievable in low-input environments. Increasing intraspecific diversity would promote community stability but would not systematically increase production. These approaches pave the way for the design of multi-species grasslands adapted to different soil and climate conditions and the definition of varietal ideotypes designed for their use in mixture with other species.