Résumé
To comply with the intensive industrial agriculture model of the Green Revolution, the modern plant breeding combines professionalized variety selection using germplasm conserved ex situ and commercial production of seeds. This model has been widely adopted in the North and very partially in the South because it is based on strong policies options and investments not tailored for developing countries. The Convention on Biological Diversity in 1992 offers an alternate approach to current varietal research with the raise of the concept of “agrobiodiversity” that promotes forms of agriculture able ensuring maintenance of genetic resources for the future. Using actual examples, this chapter illustrates advances in different plant breeding situations for crops predominantly cultivated by family farmers. In forest areas farmers are involved in the processes of creating and disseminating new varieties of coffee and cocoa while maintaining sustainable their agroforestry systems that give them advantages when price in international markets fluctuates. In dry areas with high population growth and weak agricultural production, emphasis is given to participatory breeding methods for traditional food crops which have high adaptation and multiple traditional uses, for example, sorghum in Africa and quinoa in Chile. Finally, this chapter discusses how research, through companion modeling, encourages local seed production systems, and promotes their development by enhancing knowledge exchanges between actors and creating new partnerships.