Genetic Resources and Crop Evolution

, Volume 50, Issue 5, pp 519–528 | Cite as

Yam (Dioscorea ssp.) domestication by the Nago and Fon ethnic groups in Benin

  • H.D. Mignouna
  • A. Dansi


Guinea yams (Dioscorea cayenensis-rotundata complex; D. rotundata Poir. and D. cayenensis Lam.) have been described as resulting from a process of domestication of wild yams of the section Enantiophyllum by African farmers. Although currently practised by few farmers, the process of yam domestication is still on-going in Benin. In order to document the practices used and the indigenous knowledge maintained by Nago and Fon farmers, 27 villages were surveyed. In total, 57 farmers domesticating yam were identified, and 68 yams newly domesticated (or in domestication) were collected. Fon and Nago farmers domesticate yam mainly to widen the genetic basis of the existing diversity or for simple curiosity. Among the three wild yams species (D. abyssinica Hochst. ex Kunth, D. praehensilis Benth. and D. burkilliana J. Miège) used, D. praehensilis is the most important and the most exploited. Tuber of the wild yams are collected either in the bush (most often near the village) or in the forests (far from the village) during hunting. The domestication process consists of bringing into cultivation selected individuals which go through intense vegetative multiplication and selection procedures (over a lengthy but variable period of time) that induce morphological and biochemical changes in the plant mainly at the tuber level. Individuals resulting from these manipulations were found to be, either similar or identical to known landraces or completely new based on both morphological and isozyme analysis. Because it leads to some new cultivars, this process of domestication has potential in yam breeding and appears to be a strategy that could be useful to breeders, while developing a methodology for participatory breeding of yam.

Benin Cultivar groups Domestication Dioscorea cayenensis-rotundata complex Isozyme analysis Morphological characterisation Participatory breeding Guinea yam 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Christinck A., von Brocke K., Kshirsagar K.G., Weltzien E. and Bramel-Cox P.J. 2000. Participatory methods for collecting germplasm. Experiences with farmers in Rajasthan, India. Plant Genet. Resour. Newsl. 121: 1-9.Google Scholar
  2. Burkill I.H. 1960. The organography and the evolution of the Dioscoreaceae, the family of the yams. Journal of Linnean Society (Botany) 56: 319-412.Google Scholar
  3. Dansi A., Zoundjihékpon J., Mignouna H.D. and Quin M. 1997.Collecte d'ignames cultivées du complexe Dioscorea cayenensis-rotundata au Bénin. Plant Genet. Resour. Newsl. 112: 81-85.Google Scholar
  4. Dansi A., Mignouna H.D., Zoundjihékpon J., Sangare A., Asiedu R. Quin F.M. 1998a.Varietal identification key of the cultivated yams (Dioscorea cayenensis-Dioscorea rotundata complex) of Benin Republic. Plant Genet. Resour. Newsl. 116: 18-25.Google Scholar
  5. Dansi A., Zoundjihékpon J., Mignouna H.D. and Quin M. 1998b. Approche participative pour une conservation durable des resources génétiques des ignames au Bénin. IPGRI Newsl. for Sub-Saharan Africa 10: 8-9.Google Scholar
  6. Dansi A., Mignouna H.D., Zoundjihekpon J., S angare A., Asiedu R. and Quin F.M. 1999. Morphological diversity, cultivar groups and possible descent in the cultivated yams (Dioscorea cayenen sis-Dioscorea rotundata complex) of Benin Republic. Genet. Resour. Crop Evol. 46: 371-388.Google Scholar
  7. Dansi A., Mignouna H.D., Zoundjihekpon J., Sangare A., Asiedu R. and Ahoussou N. 2000a. Using Isozyme Polymorphism for Identifying and Assessing Genetic Variation in Cultivated Yam (Dioscorea cayenensis /Dioscorea rotundata complex) of Benin Republic. Genet. Resour. Crop Evol. 47: 371-383.Google Scholar
  8. Dansi A., Mignouna H.D., Zoundjihekpon J., Sangare A., Ahous-sou N. and Asiedu R. 2000b. Identification of some Benin Republic's Guinea yam (Dioscorea cayenensis /Dioscorea rotun-data complex) cultivars using Randomly Amplified Polymorphic DNA. Genet. Resour. Crop Evol. 47: 619-625.Google Scholar
  9. Dansi A., Mignouna H.D., Pillay M. and Zok S. 2001. Ploidy variation in the cultivated yams (Dioscorea cayenensis-Dios-corea rotundata complex) from Cameroon as determined by Flow cytometry. Euphytica 119: 301-307.Google Scholar
  10. Dansi A., Pillay M., Mignouna H.D., Dainou O., Mondeil F. and Moutairou K. 2000c. Ploidy level of the cultivated yams (Dios-corea cayenensis /D. rotundata complex) from Benin Republic as determined by chromosome counting and flow cytometry. African Crop Science Journal 8: 355-364.Google Scholar
  11. Dansi A. 2000. Farmers know-how in yam production in the Republic of Benin. Report on a FAO-CIRAD sponsored Project. 150 p.Google Scholar
  12. Dumont R. 1998. Domestication des ignames en Afrique. In: Berthaud J., Bricas N. and Marchand J.-L. (eds), L'igname, Plante Seculaire et Culture d'avenir., pp. 119-123.Google Scholar
  13. Dumont R. and Vernier P. 2000. Domestication of yams (Dioscorea cayenensis-rotundata) within the Bariba ethnic group in Benin. Outlook on Agriculture 29: 137-142.Google Scholar
  14. Gottlieb D. 1982. Conservation and duplication of isozymes in plants. Science 216: 373-380.Google Scholar
  15. Gower J.C. 1985. Measure of similarity, disimilarity and distance. In: Kotz S. and Johnson N.L. (eds), Encyclopedia of Statistical Sciences Vol. 5. Wiley, New York, pp. 297-405.Google Scholar
  16. Hamon P. 1987. Structure, origine génétique des ignames cultivées du complexe Dioscorea cayenensis-rotundata et domestication des ignames en Afrique de l'Ouest. Thèse de Doctorat ès-Sciences, Université Paris XI, Centre d' Orsay 223 p.Google Scholar
  17. Hamon P., Brizard J.P., Zoundjihekpon J., Duperray C. and Borgel A. 1992. Etude des index d'ADN de huit espèces d'ignames (Dioscorea spec.) par cytométrie en flux. Canadian Journal of Botany 70: 996-1000.Google Scholar
  18. Hamon P. and Toure B. 1990a. Characterisation of traditional yam varieties belonging to the Dioscorea cayenensis-rotundata com-plex by their isozymic patterns. Euphytica 46: 101-107.Google Scholar
  19. Hamon P. and Toure B. 1990b. The classification of the cultivated yams (Dioscorea cayenensis-rotundata complex) ofWest Africa. Euphytica 47: 179-187.Google Scholar
  20. Hamon P., Dumont R., Zoundjihekpon J., Tio-Toure B. and Hamon S. 1995. Les Ignames Sauvages d'Afrique de L'Ouest. Caracteres Morphologiques. ORSTOM-Editions, Paris, France, 84 p.Google Scholar
  21. IPGRI/IITA 1997. Descripteurs de L'igname (Dioscorea spp.). Institut International d'Agriculture Tropicale, Ibadan, Nigeria / Institut International des Ressources Phytogenetiques, Rome, Italy. 65 pp.Google Scholar
  22. Lev L.S. and Shriver 1998. A trend analysis of yam production, area, yield and trade (1961-1996). In: Berthaud J., Bricas N. and Marchand J.-L. (eds), L'igname, Plante Seculaire et Culture d'avenir., pp. 11-20.Google Scholar
  23. Miege J. 1952. Contribution à L'étude Systématique des Dioscorea d'Afrique Occidentale Thèse de Doctorat ès-Sciences, Paris. 266 pGoogle Scholar
  24. Mignouna H.D., Dansi A. and Zock S. 2000. Morphological and isozymic diversity of the cultivated yams belonging to Dioscorea cayenensis and Dioscorea rotundata of Cameroon. Genet. Re-sour. Crop Evol. (in press).Google Scholar
  25. Orkwor G.C., Asiedu R. and Ekanayake I.J. 1998. Food Yams. Advances in Research. IITA and NRCRI, Nigeria, 249 p.Google Scholar
  26. Ramser J., Weising K., Lopez-Peralta C., Terhalle W., Terauchi R. and Kahl G. 1997. Molecular marker-based taxonomy and phylogeny of Guinea yam (Dioscorea rotundata-Dioscorea cayenensis). Genome 40: 903-915.Google Scholar
  27. Rohlf F.J. 1993. NTSYS-pc. Numerical taxonomy and multivariate analysis system. Exeter, New York.Google Scholar
  28. Sneath P.H.A. and Sokal R.O. 1973. Numerical taxonomy. Freeman, San Francisco.Google Scholar
  29. Swofford D.L. and Olsen G.J. 1990. Phylogeny reconstruction. In: Hillis D.M. and Moritz C. (eds), Molecular systematics. Sinauer Associates, Sunderland, Mass, pp. 411-501.Google Scholar
  30. Tanksley S.D. and Orton T.J. 1983. Isozyme in Plant Genetics and Breeding. Elsevier, Amsterdam.Google Scholar
  31. Terauchi R., Chikalake V.A., Thottapilly G. and Hahn S.K. 1992. Origin and Phylogeny of Guinea yams as revealed by RFLP analysis of chloroplast DNA and nuclear DNA. Theor. Appl. Genet. 83: 747-751.Google Scholar
  32. Vernier P. and Dansi A. 2000. Participatory asseessment and farmers knowledge on yam varieties in Benin Potential of root th crops for food and industrial resources. 12 Symposium of the International Society for Tropical Root Crops (ISTRC). Tsukuba, Japan, 10-16 sept. 2000. (in press).Google Scholar
  33. Zoundjiékpon J. and Tio-Touré B. 1992. Collecting wild yams in West Africa. Cameroon and Côte-d'Ivoire. FAO/IBPGR Plant Genetic Resources Newsletter 90: 39-41.Google Scholar
  34. Zoundjiékpon J., Hamon S., Tio-Touré B. and Hamon P. 1994. First controlled progenies checked by isozymic markers in cultivated yams Dioscorea cayenensis-rotundata. Theoretical and Applied Genetics 88: 1011-1016.Google Scholar

Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • H.D. Mignouna
    • 1
  • A. Dansi
    • 2
  1. 1.International Institute of Tropical Agriculture (IITA)IbadanNigeria
  2. 2.Crop, Aromatic and Medicinal Plant Biodiversity Research and Development Institute (IRDCAM)CotonouBenin

Personalised recommendations