Regeneration guidelines for yam

View regeneration guidelines in full (in PDF)
by clicking on the picture above (0.3 MB)

Also available in the following languages:

The information on this page was extracted from:
Dumet D. and Ogunsola D. 2008. Regeneration guidelines: Yams.
In: Dulloo M.E., Thormann I., Jorge M.A. and Hanson J., editors. Crop specific regeneration guidelines [CD-ROM]. CGIAR System-wide Genetic Resource Programme, Rome, Italy. 7 pp.

Before reading the regeneration details for this crop, read the general introduction that gives general guidelines to follow by clicking here.


Yams (Dioscorea spp.) are annual or perennial vines and climbers with annual or perennial underground tubers. They belong to the Dioscoreaceae family. This tuber-producing plant is popular in the humid and subhumid tropics, particularly in Africa, the West Indies and parts of Asia and South and Central America. Knuth (1924) estimated that there are about 600 species in the genus Dioscorea L. The most important edible yams belong to only a few species, such as D. rotundata Poir. (widely known as white Guinean yam), D. alata L. (known as water yam, winged yam or greater yam), D. cayenensis Lam. (yellow yam or yellow Guinea yam; may be composed of a complex set of different species), D. esculenta (Lour.) Burkill (lesser yam, potato yam or Chinese yam), D. dumetorum (Kunth) Pax (bitter yam or trifoliate yam), D. bulbifera L. (aerial potato yam), D. trifida L.f. (cush-cush yam), D. opposita auct. (cinnamon yam) and D. japonica Thunb.
Yams are mainly treated as annual during cultivation.Their life cycle consists of the following stages: propagules (true seed or tuber), emerging seedling or plantlet, mature plant, senescing plant and dormant tubers. Yam is generally a short-day plant. The intensity of flowering among commonly cultivated yam ranges from nil to profuse. Yams are principally
conserved vegetatively in field genebanks; efforts are also underway in some genebanks to conserve them in vitro for safety duplication.

Procedures described in this guideline refer to field collections only for the following species: D. alata, D. rotundata, D. cayenensis, D.
bulbifera, D. esculenta, D. dumetorum, D. praehensilis, D. mangenotiana
and D. bulkilliana.

Choice of environment and planting season

Yam plant. (photo: M.E. Dulloo)

Climatic conditions

Planting season

Preparation for regeneration

When to regenerate


Field selection and preparation

Method of regeneration

Propagation method

Preparation of minisets. (photos: Dominique Dumet /IITA)

Planting method (see photos below)

Yam planting. (photos: Dominique Dumet /IITA)

Planting layout, density and distance


Crop management

Stakes for crop management.
(photo: Dominique Dumet /IITA)


Weed management



Common pests and diseases

Pest and disease control




Post-harvest management

Documentation of information during regeneration

Collect the following information during regeneration:

References and further reading

Bioversity International, IITA. 2009. Key access and utilization descriptors for yam genetic resources. Bioversity International, Rome, Italy; International Institute of Tropical Agriculture, Nigeria. Available here.

Knuth R. 1924. Dioscoreaceae. In: Engler A, editor. Das Pflanzenreich 87(IV-43): 1–387.

Orkwor GC, Asiedu R, Ekanayake IJ, editors. 1998. Food Yams. Advances in Research. International Institute of Tropical Agriculture and National Root Crops Research Institute, Nigeria.


These guidelines have been peer reviewed by Alexandre Dansi, University of Abomey-Calavi, Benin, and Perla Hamon, Institute de Recherche pour le Développement (IRD), France.

The Genebanks

The 11 CGIAR genebanks currently conserve 730,000 of cereals and grain legumes, forage crops, tree species, root and tuber crops, bananas and crop wild relatives.