My works concerned landscape management by the agricultural companies such as farms and cooperatives. At farm level I produced a conceptual model of management strategies that take into account the organization of the production, the constraint coming from landscape characteristics and objectives of landscape transformation. This framework is then used for several models that connect management sciences and agronomy. For the management of landscape by cooperatives the question of GM and non GM coexistence was a situation where it was possible to analyze the individual and collectives strategies that organized the landscape in order to minimize GM and non GM mixing. A model of cooperatives management strategies connected with gene flow model allows to evaluate the efficiency of the strategies and to show the necessity of cooperation between these companies in order to avoid a loss of value for all the agricultural companies.
