Molecular breeding bases of trifoliate yam (Dioscorea dumetorum (Kunth) Pax) post-harvest hardening phenomenon of tubers

Yams (Dioscorea spp.) are important and economical food for millions of people in the tropics and subtropics. However, its cultivation is jeopardized by the post-harvest hardening (PHH) phenomenon characterized by the inability of tubers to soften during cooking. The main objective of this thesis was to provide the basis of genetic breeding for avoidance of the PHH in D. dumetorum. Firstly, using genotyping-by-sequencing, we showed that D. duemtorum accessions in Cameroon are diverse. Secondly, based on long reads sequencing technologies, we released the first and highly contiguity D. dumetorum genome sequence. Finally, harnessing the D. dumetorum genome sequencing and using transcriptome analysis, we demonstrated that genes are differential and up regulated after harvest. The significance of this study is that it defines the framework for the improvement of PHH avoidance and for other significant characters in yam as well as for yam conservation.