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.

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For the estimation of genetic parameters (such as heterosis effect, potence ratio, combining ability and reciprocal effects) of five fruit traits, in order to suggest breeding strategies in Citrullus mucosospermus (Fursa), a field trial was carried out at Kononfla city in Western Côte d'Ivoire using 4x4 full diallel. All 12 F 1 hybrids and their parents were planted in a randomized complete block design with three replications. A positive heterosis effect relative to mid-parental values was observed to hybrids having one parent Bebu for characters' fruit weight, fruit diameter and fruit volume. Variances due to general (GCA) and specific (SCA) combining abilities were significant (P˂0.001) for all studied traits, indicating the involvement of both additive and non-additive gene actions in the inheritance of these traits. Non-additive gene effects were predominant for all studied traits. Bebu was the best general combiner for all traits except fruit number which the best combiners were three morphotypes of Wss. For NF, Wss1×Wss2 and Wss2×Wss3 recorded the highest positive SCA values. Crosses involving Bebu as one parent, presented the best SCA values for other traits.