Résumé
The project aims at the genetic improvement of the vegetatively propagated greater yam through the integrated techniques of biotechnology and conventional breeding, developed by the CIRAD and the CTCRI respectively. Selection of fertile parents will be facilitated by identifying tetraploid cultivars through cytological studies and estimating their genetic diversity by DNA fingerprinting (AFLP & SSRs). The genetically distant cultivars will be hybridized to maximize heterosis in the progeny. Pollen grains from elite males will be preserved for pollinating superior females that flower at different periods. Large scale seed production will be effected through the joint efforts of scientists from the partner institutes. Among the resulting sexual progeny, DNA markers will be identified to select superior recombinants at the early stages. The relevance of the project is the integration of two complementary technologies in the genetic improvement of greater yam, for the first time. As this important food crop is dioecious, vegetatively propagated and under-studied, many constraints have so far hindered its genetic improvement. By the complementary strategies of CTCRI and CIRAD, the existing constraints will be easily overcome and the production of genetically improved, superior varieties will be easier and quicker. (Résumé d'auteur)