Résumé
Understanding the complex dynamics of fruit growth is crucial for optimizing agricultural practices and improving food production. Observational difficulties pose a challenge to the development of models capable of providing a description of the cellular processes involved, while reproducing the macroscopic observables of interest. Here we present a mechanistic framework for modeling the growth of fleshy fruits. The framework integrates single cell expansion and division processes with organ-wide resource sharing processes. Using empirical data on tomato fruit growth under different irrigation and fruit charge regimes, our model accurately reproduces the temporal patterns of total cell number and fruit mass, and predicts cell mass distributions at harvest. The framework allows for the separation of the effects of genotypic and environmental factors on the parameters related to the biological processes. This sheds light on the possible relationship between genetic traits, growth conditions and fruit quality traits. In addition, our framework provides insights into the possible mechanisms of nutrient optimization and offers valuable implications for improving agricultural practices. Our study provides a unified approach to fruit growth that can be applied beyond tomato to other multicellular proliferating populations characterized by resource sharing.