Usages traditionnels et valeur économique de Synsepalum dulcificum au Sud-Bénin

Abstract

Synsepalum dulcificum (Schumach. & Thonn. Daniell) is a West African shrub which is listed as vulnerable by the IUCN. Its importance for local people in Benin has been little documented. This study takes up this issue and was carried out to assess local knowledge, use value and the economic importance of the species for local people. Ethnobotanical and economic surveys were conducted with 606 respondents from 13 socio-cultural groups in southern Benin. Ethnobotanical and economic indices (citation frequency, ethnobotanical use value and mean income generated) were computed and their significance tested using generalized linear models and Kruskal and Wallis tests. The results showed that S. dulcificum was well known to local people in southern Benin (100% of respondents), who mostly grew it in their home gardens. All parts of the plant were used, mostly for medicinal, food and spiritual purposes. Knowledge of the shrub and its use value varied among the socio-cultural groups, decreasing along a gradient from south-east to south-west. Knowledge and use value were also dependent on gender, age and activity, and concentrated among men, adults, elderly people and traditional healers. Economic data showed a short marketing chain. The low average income generated by selling the fruit (about US$ 28 yearly per seller) reveals the low economic value of the species, which is a declining subsistence resource. Optimising the conservation and uses of the species would require (i) nutritional, phyto-chemical, pharmaceutical, phenological, morphological and genetic investigations, (ii) the development of sylvicultural method, (iii) inclusion of the species in formal conservation policies and (iv) development of a value chain by establishing a structured production channel.