Bien que plusieurs fruitiers sauvages aient été étudiés au Bénin, d’autres, dont Cola millenii K. Schum., y demeurent peu documentés. Cette étude avait pour objectif d’inventorier les connaissances ethnobotaniques de C. millenii par les groupes socioculturels béninois. Des entretiens individuels structurés ont été menés auprès de 1 009 personnes. La fréquence relative de citation et l’indice d’efficacité ont été utilisés pour apprécier respectivement l’importance relative de chaque utilisation et le niveau d’efficacité de la plante dans le traitement d’une maladie donnée. C. millenii relève de huit catégories d’usage. L’usage alimentaire de la pulpe du fruit est le plus pratiqué. Le paludisme est la maladie la plus citée. Globalement, l’espèce serait très efficace dans le traitement du paludisme, de l’ictère, des maux de ventre, de l’hypertension, des courbatures, de la fatigue, de la fièvre et du vertige ; moyennement efficace dans le traitement de l’asthme, des troubles liés à la grossesse et de l’enflure des pieds ; mais peu efficace contre l’oligospermie. La feuille est la partie la plus utilisée et la décoction est le mode de préparation le plus employé dans le traitement des maladies. Les Anii et Chabè préfèrent l’usage alimentaire de l’espèce tandis que son usage à des fins magiques et comme brosse végétale ou bois de service est privilégié par les Adja et Kotafon. Par contre, les Aïzo l’utilisent plus à des fins médicinales, et son usage comme bois d’œuvre est plus important pour les Mahi. Les feuilles et les fruits sont les parties les plus commercialisées. Malgré son importance, l’espèce subit diverses pressions et bénéficie très peu de mesures de conservation. Des recherches futures devraient se pencher sur sa sylviculture pour assurer sa domestication.

The structural characterization ofProsopis africanaof Benin was studied on the basis of forest inventory conducted in three different vegetation types (savannah, fallow, and field) and three climate zones. The data collected in 139 plots of 1000 m²each related to the diameter at breast (1.3 m above ground), total height, identification, and measurement of DBH relatedP. africanaspecies height. Tree-ring parameters such as Blackman and Green indices, basal area, average diameter, height of Lorey, and density were calculated and interpreted. Dendrometric settings of vegetation type and climate zone (Guinea, Sudan-Guinea, and Sudan) were compared through analysis of variance (ANOVA). There is a significant difference in dendrometric settings according to the type of vegetation and climate zone. Basal area, density, and average diameter are, respectively, 4.47 m²/ha, 34.95 stems/ha, and 37.02 cm in the fields; 3.01 m²/ha, 34.74 stems/ha, and 33.66 cm in fallows; 3.31 m²/ha, 52.39 stems/ha, and 29.61 cm in the savannahs. The diameter distribution and height observed at the theoretical Weibull distribution show that the diameter and height of the populations of the species are present in all positively skewed distributions or asymmetric left, a characteristic of single-species stands with predominance of young individuals or small diameters or heights.

In West Africa, and Benin particularly, local forest resources can potentially contribute to both increasing and stabilizing soil productivity. However, these resources continue to be neglected with efforts instead concentrated on promoting exotic species. This study aimed to prioritize local agroforestry species on agricultural landscape by investigating the gendered, socio-demographic and agro-pedological factors of local knowledge and use of agroforestry species amongst small-holder farmers in Benin. An agroforestry inventory combined with an ethno-agroforestry survey was conducted on 364 farms with 364 farmers. A cluster analysis based on farmers' socio-demographic and agroecological factors was used to cluster farmers into two homogeneous agroforestry systems. Median score, species diversity and ecological networks were established for these two systems. Results illustrate that gendered difference exist between the priority that farmers give to multi-purpose species and this prioritization depends on priority ecosystem services for farmers and gender. Therefore, it would be useful first to consider gender and specific needs of each category of farmer to optimize the choice of agroforestry species to be promoted in such systems. The successful introduction of identified species through extension programs requires more advanced research related to the real contribution of these species to farmland fertilization, as well as the nutrient transmission pathways to associated crops in an agroforestry system to address simultaneously specific ecological, economic and socio-cultural sustainability criteria, as well as improved crop production.

Variations of climate conditions challenge germination of Kigelia africana seeds and growth across its distribution range. This study assessed the influence of provenances (with varied climate conditions) and seed storage duration on seed germination and seedling growth across three climatic zones in Benin. A three-way randomized complete block design was established, including seed provenances, storage duration (freshly collected, one-year and two-year storage), and seed soaking duration (0, 24 and 48 h). Nine treatments were applied to seeds from three provenances, each repeated three times. The number of seeds germinated per treatment was recorded daily, as were the time to first germination and the average germination duration. Seedlings were transplanted and growth parameters such as height, stem diameter, and number of leaves were measured weekly for 12 weeks. The results showed that no seed stored for two years germinated. The mean germination rates of freshly collected seeds and seeds stored for one year were 65.22% and 57.22%, respectively. Freshly collected seeds, whether soaked for 24 h or not, significantly affected positively seedling height (estimate = 0.12, p < 0.001) and stem diameter (estimate = 0.06, p < 0.001). These results provide important insights for the conservation of Kigelia africana through climate-zone-specific approaches.