Agro-morphological characterization of beans of the phaseolus genus and identification of their cultivated species in Benin (West Africa)

The local cultivars of the Phaseolus genus present within the local communities constitute a considerable source of genes and consequently of genetic diversity which would lead to success of the varietal creation of beans. Nevertheless, these resources suffer from a significant genetic erosion because of the climatic requirement but also of the difficulties related to their cultivation methods. The objective of this study is to identify the phenotypical distinctive features of the species of the Phaseolus genus cultivated in Benin for a permanent management. To achieve this goal, an agro-morphological characterization was carried out on two years (2019-2020) from March to August of each, at Ahossougbéta (Abomey-Calavi) following a completely randomized blocks design with three replications. Data were collected on twenty-three measured characters on 88 accessions. Data were subjected to the descriptive analysis, the analysis of variance and the multivariate analyses. Results showed a great variability among the accessions for the studied cultivars. Three major groups were identified and were characterized by the AFD. The studied cultivars were characterized more by the shape of the first leaves, the color of the flowers, the color of the integuments, the width of the pods, times of flowering and appearance of the pods and the width and the length of the pods. These results are significantly important for the classification of beans species of the Phaseolus genus. In addition, morphological and molecular genetic characterizations are necessary within each specie in order to define strategies for the improvement and the conservation of their genetic resources in Benin.