Traditional medicinal knowledge of woody species across climatic zones in Benin (West Africa)

Abstract

Ethnopharmacological relevance: Plant parts are often used by local people to treat their affections. This study addressed the Traditional Medicinal Knowledge of woody species in Benin and the dependence of medicinal use of woody species on climatic zones.

Aim of the study: It reports (i) the main diseases categories treated with medicinal use of woody species in Benin and changes across climatic zones by inferring their epidemiological status, and (ii) the woody species involved and their distribution according to climate conditions.

Materials and methods: Ethnobotanical interviews were undertaken using a semi-structured questionnaire. Five hundred and ninety medicinal plant professionals (healers, traders …) were interviewed in the whole country. Frequency of citation and informant consensus factor were calculated to highlight the main human diseases categories and woody species used for their treatment. A principal component analysis was performed to determine the occurrence of diseases categories in different climatic zones.

Results: About 94% of international diseases categories were treated using medicinal woody species in Benin. Nighty-seven ailments in 16 diseases categories were identified. Among them, 5 diseases categories (General and unspecified, Digestive, Skin, Neurological, and Musculoskeletal) were highlighted as important. The Sudano-Guinean zone showed the highest diseases frequencies, whereas the Sudanian zone showed the lowest. The epidemiological status of some phytodistricts was worrisome. In our study, 123 woody species belonging to 93 genera and 35 families were reported, and among them, 16 were the most used as treatments.

Conclusions: There is a lack of consensus among traditional healers about which woody species to use. Many different species were used to treat a given diseases category. Also, information concerning their organ composition was not available in the literature, for the majority of species. Biological and chemical investigations are thus needed for a better valorization of the most frequently used plants in the future.

Keywords: Climatic zone; Phytodistricts; Traditional medicinal knowledge; Woody species.