Modelling intercrops functioning to advance the design of innovative agroecological systems

Abstract The growing demand for sustainable agriculture is raising interest in intercropping for its multiple potential benefits. Predicting the existence and magnitude of those benefits remains a challenge given the numerous interactions between the plants, their environment and the agricultural practices. Crop models are crucial to understand and predict such interactions, yet few are able to simulate bi-specific intercrops correctly, mainly because they contradict assumptions used to simulate sole crops.In this study, we propose simple and generic formalisms for key interactions in intercropping systems that can be readily included into existing dynamic crop models. We provide an implementation into the STICS soil-crop model with an independent evaluation of the consistency and genericity of the combined formalisms under a wide range of conditions. Simulations were close to observations for all situations (nRMSE = 25% for max. LAI, 22% for shoot biomass at harvest, and 17% for yield), which showed the consistency and accuracy of the proposed formalisms despite their relative simplicity.