Attempts to control potato late blight with cattle slurry

agriculture biologique application date control de enfermedades crop yield danemark date d'application denmark dinamarca disease control disease resistance feuille field experimentation hojas infection leaves lisier nitrogen content organic agriculture phytophthora infestans radiation solaire rendement des cultures rendimiento de cultivos resistencia a la enfermedad slurry solanum tuberosum solar radiation teneur en azote tubercule tubers variedades varieties