Greater yam (Dioscorea alata L.) is a tuber crop, with a pantropical distribution which can mainly be explained by its ease of cultivation and broad tolerance to different environments. It is a crop of utmost importance in many regions of developing countries, where it could be the only source of carbohydrates available. Despite its importance, little was known about this species. At CIRAD, we first conducted research on its reproductive biology, which allowed us to determine its ploidy level, the genetic control of flowering and sex determination. We also worked on its genetic diversity and demographic history. In parallel, we are currently working on the development of medium and high-throughput phenotyping methods. These findings are now being deployed to carry out our work in deciphering the genetic determinism of the traits related to yam quality using different approaches. Indeed, despite its ability to adapt to different environments, greater yam has a lower organoleptic quality in comparison with the African guinea yam species (D. rotundata Poir.). In West Africa, the most yam-consuming region, the quality requirements are very high which can be a factor in the rejection of new varieties if the quality criteria of the consumers are not met. In this seminar,

I will present our main results and the areas of research on which we are currently working for theyam genetic improvement for quality. This seminar is a preface to the PhD defense of Narccisse Denadi (open to all, CARNOY B059, 16:15): “Déterminisme du sexe chez les ignames cultivées Dioscorea rotundata (Poir.) du Bénin”