Effect of Crop Growth and Susceptibility on the Dynamics of a Plant Disease Epidemic: Powdery Mildew of Grapevine

For a better understanding of host / pathogen dynamical interactions and of the capacity of host development to modify disease progress, we devised epidemiological simulation models coupling plant growth with the dispersal and disease dynamics of an airborne plant pathogen. Our first model is a complex discrete deterministic model that explicitly incorporates the dynamics of host growth (e.g., distance between organs and their susceptibility) and the development and dispersion of the pathogen. The second one is a much simpler compartmental SEIR-like model. It takes into account the host growth with the foliar surface as unit of host growth and the ontogenetic resistance of the leaves. We compare the output of both models when applied to the specific system formed by the powdery mildew, Erysiphe necator, of grapevine.