Supervisor: Simon Joly
Yams are one of the principal sources of nutrition in West Africa and their extended storage capacity contributes to food security in the region during periods of food scarcity. Yams reproduce by clonal multiplication and local farmers use the tubers from their harvest as seed for the following season. Although this method has the advantage of providing farmers with a ready source of tubers for planting, it also increases the likelihood of disseminating plant pathogens which can have catastrophic effects on the quality of the harvest. The absence of sexual reproduction means that the evolution of the species is very slow and its capacity to adapt to changing environmental conditions and resist disease is limited. The increase in the destruction of indigenous forests is leading to a reduction of wild yam species Further, as farmers cultivate only a small number of species, the genetic diversity of Dioscorea is gradually being eroded. In order to preserve the genetic resources of this genus. Yam's tubers will be collected in three regions of Cameroon, then cultivated in an experimental field. Dry leaf samples of each species will be use for DNA extraction. These DNA fragments will then be amplified and sequenced so that, using bioinformatics software. The degree of relatedness will be determine within and between species and hence the genetic diversity of this genus. On the other hand, different tissue culture techniques will be test with the same yams species in order to produce of microtubers which could be used both to conserve the genetic diversity of Dioscorea in a seed bank and as a commercial source of seed for farmers.