A participatory plant breeding (PPB) program involving the French farmers' association ‘Réseau Semences Paysannes’ and the French National Agricultural Research Institute (INRA) at Le Moulon was initiated in 2005. In the process of designing the breeding scheme, we evaluated the impact of farmer selection at an early stage (F2) on bread wheat cross progeny populations. The objectives were to characterize the effect of farmer selection, to evaluate the impact of farmer selection on intra-varietal diversity, to provide farmers with relevant information that they can use to improve their selection practices. Early selection was found efficient for some traits and for some of the 35 F2-derived F3 families. For traits of interest such as thousand kernel weight or grain weight per spike, when the response was significant, it was always positive. For most of the traits studied, the among-family genetic variance increased after selection while the average within-family genetic variance decreased. This study provides the first quantitative results for this PPB program and information that will help optimize it in the future.