RESUMEN
Fifty (50) villages randomly selected throughout agroecological zones in Togo were surveyed, using participatory approach, to identify and prioritize factors that affect production and farmers’ varietal preference criteria of Guinea yam (Dioscorea cayenensis-D. rotundata complex). A total of nineteen (19) constraints of varying importance across agro-ecological zones were identified among which the most important were insects’ damages on both leaves and tubers, nematodes attack on tubers, drought, soil poverty and wilting. For the majority (78.94%) of the constraints, the use of tolerant cultivars remains the most sustainable, economically profitable and environment preservative solution. Farmers’ cultivar preference criteria identified are many (24 in total). Among them, high productivity, good quality of pounded yam, resistance to drought and adaptability to all types of soils are the most important. A perfect match is noted between enumerated constraints and identified preference criteria. The knowledge of farmers’ selection criteria is of capital importance for breeders and also extension services for eventual yam cultivar exchange between agroecological zones in Togo.