A knowledge of the extent of genetic variation in a crop is a prerequisite for its improvement. In cassava (Manihot esculenta Crantz) such knowledge is lacking especially at the DNA level. The genetic variation among 28 cassava varieties collected from different locations in the Republic of Benin was investigated using random amplified polymorphic DNA (RAPD). A set of 10 random sequence 10-mer primers out of 100 that were screened detected polymorphisms and generated 78 amplified DNA bands. Based on an unweighted pair group method with arithmetic averages (UPGMA) cluster analysis, the accessions were categorised into 6 groups. The results, summarised in a dendrogram, show the genetic diversity among this cassava germplasm.La connaissance de l'importance de variation genetique chez une culture est necessaire pour son amelioration. Chez le manioc (Manihot esculenta Crantz), une telle connaissance manque surtout au niveau du DNA. La variation genetique parmi les 28 varietes du manioc recueillies de differentes localites du Benin etait etudiee en utilisant un polymorphe amplifie selectif du DNA (RAPD). Un ensemble de 10 amorces de 10-mer d'une selection sequentielle sur 100 qui avaient ete depistes ont detecte le polymorphisme et ont genere 78 bandes de DNA amplifie. Sur la base de l'analyse de faisceau de la methode d'un groupe de paire non-pondere avec les moyennes arithmetiques (UPGMA), les varietes etaient divisees en six groupes. Les resultats, resumes en dendogramme, montrent la variation genetique chez les differents types du plasme germinatif du manioc

Cassava; Plant Breeding; Genetic Improvement; Impact Assessment

Cultivar Identification; Genetic Variation; Manihot Esculenta; Rapd; Identification Varietale; Variation Genetique

Africa; West Africa

Benin