Résumé
In France, farmers may use only registered crop varieties, listed in the annual French or European official catalogue of species and varieties. For arable species, that represents the context of this paper, a variety is defined by official legislation as being distinct, uniform and stable (DUS) and is evaluated for its value for cultivation and use (VCU) on environments homogenized by an intensive cropping system. The evaluation is mainly focused on the yield and the industrial quality. But new demands are emerging resulting in -or in response to- the diversification of agriculture. Consequently the demand for a diversity of varieties well adapted to new cropping system and to new outlets is increasing. Our objective is to study the equilibrium between variety offer and demand and how the breeding system may fit the needs. The offer is appreciate by the evolution, over the time, of the number of varieties proposed in the catalogues and by the evolution of the number and of the identity of breeding actors. The number of varieties has greatly increased while the number of breeding firms (essentially private firms) is decreasing. The new demand of variety was studied through several enquiries and is represented by 4 models. Each model needs specific breeding scheme and relevant breeding actors. These different ways to envision varieties and plant breeding must not preclude one another but must be considered as complementary and able to renew the way to implement plant improvement for agriculture. In such context, public institute have a great role to play and mainly in the development of participatory plant breeding projects.