Diversity, cultural practices and domestication of Sesamum radiatum Thonn. ex Hornem and Justicia tenella (Nees) T., two neglected and underutilised traditional leafy vegetables consumed in Benin

Abstract

Sesamum radiatum and Justicia tenella are two traditional leafy vegetables highly consumed in Benin. In spite of their importance in food security, nutrition, and income generation, they still remain very little known to the scientific communities. In order to document their diversity and the various traditional cultural practices associated with their production and identity as well as their domestication levels across zones, a survey was conducted in 10 villages randomly selected from different agroecological and ethnic zones of both northern and central Benin. Data were collected in the different sites through application of Participatory Research Appraisal tools and techniques and analysed using both simple descriptive statistics (means, frequencies, etc.) and multivariate analysis (ANOVA, cluster analysis). The study revealed the existence of clear intraspecific diversity within J. tenella contrarily to S. radiatum for which no apparent diversity was noted. In most of the households surveyed, J. tenella and S. radiatum were found respectively at steps 3 and 4 in the domestication process. The production of these vegetable species is still traditional and biologic (no fertilisers, no pesticides). The cultural practices used are not the same for the two species and vary between households and between ethnic groups. The multivariate analyses (Cluster analysis, PCA) conducted based on the various traditional farming practices to examine the relationship between farmers revealed respectively 4 and 5 categories of producers of J. tenella and S. radiatum corresponding to the same numbers of applied traditional technological packages. Further domestication trials were recommended to develop the best technical packages required to master mass production of the species in the future for the benefit of both producers and consumers. Agromorphological and genetic characterisation were also recommended in order to establish the scientific basis for their varietal improvement.