Abstract
In the traditional yam agricultural system, by way of an ennoblement practice, farmers select tubers from the wild for cultivation. In order to assess the impact of that practice on the genetic diversity of yam, we studied the genetic structure of yams obtained after at least 3 years of ennoblement, to which farmers gave the name of traditional varieties. Cultivated yams do not always have the same genotype as homonymous traditional varieties. For the first time, we demonstrated selection by farmers through the ennoblement of genotypes found in neighbouring villages. Their adoption has a double impact: it allows an increase in the polyclonality of varieties and an indirect exchange of yam tubers between farmers. We also demonstrated that wild yams and hybrids between wild and cultivated yams are also selected. However, their adoption seems less frequent, suggesting selection and valuation of ennobled yams before integration into the cultivated pool. Finally, the adaptive advantage of wild and hybrid yams and their role in yam agrosystems are discussed.
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Notes
Ennoblement was initially described under the unsuitable term of domestication.
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Acknowledgments
This research was supported by the Centre de Coopération Internationale en Recherche Agronomique pour le Développement and partly by the Beninese “Programme de Développement des Racines et Tubercules”. Part of this work was carried out using the resources of the Computational Biology Service Unit from Cornell University. We thank B. Fatondji and A. Bouet for their technical assistance. We gratefully acknowledge X. Perrier for his critical reading of the manuscript. Our greatest debts go to the farmers in the villages investigated in northern Benin for their interest in participating in our study and for providing us with valuable plant material.
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Chaïr, H., Cornet, D., Deu, M. et al. Impact of farmer selection on yam genetic diversity. Conserv Genet 11, 2255–2265 (2010). https://doi.org/10.1007/s10592-010-0110-z
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DOI: https://doi.org/10.1007/s10592-010-0110-z