Collection and characterisation of plant materials is a crucial step in crop improvement programmes. The objective of this study was to characterise a sweet potato (Ipomoea batatas [L.] Lam.) collection from the Centre National de Recherche Agronomique (CNRA) in Côte d'Ivoire, based on morphological characters, and to elucidate the relationships among them. The experiment was carried out in a Fisher design with two replications. The descriptive analyses revealed a substantial phenotypic variation within the collection. The multiple correspondence analysis showed that 15 characters out of 27 were the most discriminant to explain the variation. Furthermore, significant relationships were observed between phenotypic traits related to leaves, stems and storage roots. The hierarchical classification placed accessions into three genetic groups regardless of their geographical origin and revealed the existence of duplicate accessions. The results obtained could be used for the selection, improvement and sustainable management of sweet potato genetic resources.

The objectives of this study were to assess phenotypic diversity of Bambara groundnut germplasm from Côte d'Ivoire using qualitative traits and to understand the genetic diversity at different levels. Hundred and one accessions collected from four agro-ecological zones (central, eastern, northern, western) were characterized in a randomised complete block design with three replications. Thirteen qualitative traits were recorded from seedling emergence to physiological maturity of the crop species. All recorded traits were found to be polymorphic with three or four phenotypic classes. The results revealed a considerable amount of phenotypic variation in the germplasm studied. The phenotypic variation was expressed in color, shape, texture, flexibility, growth habit, pilosity and hardness in both the aerial organs and the underground pods. Cluster analysis grouped together accessions into six genetically distinct groups independently to their geographical origin, suggesting seeds exchanges between growing-zones. The chi-square analysis highlighted the presence of phenotypic variability within and between accessions from each agro-climatic zone for most of the traits evaluated indicating some adaptive forms related to the four zones. Estimates of Shanon-Weaver diversity index (H') for all agro-climatic zones ranged from 0.32 to 0.66 with a mean of 0.46. The northern zone appeared phenotypically more diversified (H' = 0.66) than the others. These results are useful to ensure efficient germplasm collection, conservation and management strategies.