Cultural practices for characterization of wild rice

Contributors to this page: T.T. Chang Genetic Resources Centre-IRRI, Los Baños, Philippines (Ruaraidh Sackville Hamilton, Ken McNally, Flora de Guzman, Renato Reaño, Soccie Almazan, Adelaida Alcantara, Elizabeth Naredo); WARDA, Cotonou, Benin (Ines Sánchez); UPLB-University of the Philippines at Los Baños (Teresita Borromeo).

Wild rice is best characterized during the seed regeneration process. So the following cultural practices are the same as the regeneration guidelines of wild rice.

Choice of environment and planting season

Climatic conditions

Planting season

Preparation for regeneration

When to regenerate

The frequency of regeneration is determined by the quantity of seeds stocks left at the genebank.

The selection of material for planting depends upon the available space in the screen house facility as space is usualy a limiting factor.

Propagation method

Breeding system



Wild species are known to have stronger dormancy than the cultivated species. They may require one or a combination of dormancy breaking treatments including heat treatment, dehulling, exposure to alternating temperatures and, in some cases, chemical treatments.

Heat treatment


Chemical treatment

Method of regeneration

Sowing method


Planting layout, density and distance

Planting conditions

Different varieties of rice being grown inside an IRRI green house (photo: IRRI)

Crop management



Pest and disease control



Panicle bagging

Rice being grown inside an IRRI screen house. Notice the bagged panicles (photo: IRRI)

Panicle harvesting

Post harvest management

Seed processing

Disposal of contaminated material

To ensure plants do not spread by seeds or rhizomes, specific measures should be followed:

Recording information

Consult the general rice characterization page for information about descriptors, or recording of information during characterization.

References and further reading

Borromeo TH, Sanchez PL, Vaughan DA. 1994. Wild rices of the Philippines. Philippine Rice Research Institute, Maligaya, Nueva Ecija, Philippines.

Chang TT, Vaughan DA.1989. Conservation and potentials of rice genetic resources. In: Bajaj YFS, editor. Biotechnology in agriculture and forestry. Springer Verlag, Berlin.

Hanson J. 1985. Practical Manuals for Genebanks: Procedures for handling seeds in genebanks. IBPGR, Rome, Italy. HTML version available from: Date accessed: 10 June 2010.

Lu BR. 1999. Taxonomy of the genus Oryza (Poaceae): Historical perspective and current status. IRRN 24.3. IRRI, Los Baños, Laguna.

Manual of operations and procedures of the International Rice Genebank. 2000. Genetic Resources Center, IRRI. Available here.

Naredo MEB, Juliano AB, Lu BR, de Guzman FC, Jackson MT. 1998. Responses to seed dormancy breaking treatments in rice species (Oryza L.). Seed Science and Technology 26:675-689.

Rao NK, Hanson J, Dulloo ME, Ghosh K, Nowel D, Larinde M. 2006. Manual of seed handling in genebanks. Handbooks for Genebanks No. 8. Bioversity International, Rome, Italy. Available in English (1.5 MB),  Spanish (1.4 MB) and French (1.9 MB).

Reed BM, Engelmann F, Dulloo ME, Engels JMM. 2004. Technical guidelines for the management of field and in vitro germplasm collections. Handbook for Genebanks No. 7. IPGRI, Rome, Italy. Available here.

Sackville-Hamilton NRS, Chorlton KH. 1997. Regeneration of accessions in seed collections: a decision guide. Handbook for Genebanks No. 5. IPGRI, Rome, Italy. Available here.

Tateoka T. 1962a. Taxonomic studies of Oryza I. O. latifolia complex. Bot. Mag. Tokyo 75:418-427.

Tateoka T. 1962b. Taxonomic studies of Oryza II. Several species complexes. Bot. Mag. Tokyo 75:455-461.

Tateoka T. 1963. Taxonomic studies of Oryza III. Key to the species and their enumeration. Bot. Mag. Tokyo 76:166-173.

van Soest LJM.1990. Plant Genetic Resources: Safe for the future in genebanks. Impact of Science on Society 158:107-120.

Vaughan DA. 1989. The genus Oryza L. Current status of taxonomy. IRRI Research Paper Series 138, Manila, Philippines.

Vaughan DA, Sitch LA. 1991. Gene flow from the jungle to farmers. Bioscience Vol. 41(1):22-28.

Vaughan DA. 1992. The wild relatives of rice: A genetic resources handbook. IRRI, Los Baños, Philippines.

Vaughan DA, Chang TT. 1992. In situ conservation of rice genetic resources. Economic Botany 46(4):368-383.

Vaughan DA, Morishima H, Kadowaki K. 2003. Diversity in the Oryza genus. Current Opinion 6:139-146.

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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.