Protologue Bull. Mus. natn. Hist. nat., Paris 16: 405 (1911).
Family Poaceae (Gramineae)
Chromosome number 2n = 24
Synonyms Oryza breviligulata A.Chev. & Roehr. (1914), Oryza stapfii Roshev. (1931).
Vernacular names Wild rice, self-sown rice, Mandinka rice (En). Riz sauvage annuel, riz de marais, riz sauvage (Fr).
Origin and geographic distribution Oryza barthii is distributed in tropical Africa from Mauritania east to Ethiopia and south to Botswana and Zimbabwe.
Uses The grains of Oryza barthii are sometimes collected if enough plants are available, and they serve as a famine food. They are sometimes sold in markets. However, Oryza barthii is regarded mostly as a weed. Before flowering the plant provides good grazing for livestock; after flowering the awns may cause injury to the mouth.
Properties The grain of Oryza barthii has a good flavour.
Botany Annual grass up to 150 cm tall, growing in tufts; stem (culm) erect or geniculately ascending, with roots from the lower nodes, spongy, striate, glabrous. Leaves alternate, simple and entire; leaf sheath striate, smooth; ligule 26(9) mm long, truncate or rounded; blade linear, 1545 cm Χ 0.51.5 cm, with acute apex, intense green, glabrous, smooth on the lower surface, slightly rough on the upper surface. Inflorescence a terminal panicle 2035 cm Χ 37.5 cm, rather dense, erect or more rarely somewhat nodding, with erect or obliquely ascending branches. Spikelet oblong to narrowly oblong, 711 mm long (awn excluded), deciduous, pale green to straw-coloured, 3-flowered but 2 lowest florets reduced to sterile lemmas 2.54.5 mm long; glumes reduced to a 2-lobed rim; lemma of fertile floret slightly shorter than spikelet, boat-shaped, leathery, hairy, with 2 longitudinal lateral grooves, with pink to purplish stiff awn (4)816(19) cm long; palea about as long as lemma but much narrower, with the apex drawn out in a short blunt point; lodicules 2; stamens 6; ovary superior, with 2 plumose stigmas. Fruit a caryopsis (grain). Oryza comprises about 20 wild species distributed throughout the tropics and subtropics, and 2 cultivated species, Oryza sativa L. and Oryza glaberrima Steud. Oryza barthii is classified in ser. Sativae, together with Oryza sativa, Oryza glaberrima and Oryza longistaminata A.Chev. & Roehr. Oryza barthii is predominantly inbreeding, with an outcrossing rate of 520%.
Ecology Oryza barthii grows in shallow water in ponds and marshes, and as a weed in rice fields, up to 1500 m altitude. It may form pure stands, but is usually found scattered with other aquatic grasses. It may become a noxious weed and may act as a reservoir for important rice diseases and pests. Oryza barthii is a short-day plant.
Management Oryza barthii is not normally cultivated, but the grain is collected from the wild. The grain shatters very easily, and the panicles are usually collected before they are mature. If ripe, the panicles are harvested over a basket or calabash to collect falling grain.
Genetic resources and breeding Oryza barthii has a relatively narrow genetic variation. It is considered a source of resistance to various diseases affecting Oryza sativa, including bacterial leaf blight (Xanthomonas oryzae pv. oryzae), rice yellow mottle virus (RYMV) and sheath blight (Thanatephorus cucumeris, anamorph: Rhizoctonia solani).
Prospects Although Oryza barthii may serve as a famine food during times of shortage, it is probably more often considered a weed of Oryza sativa than a valuable food plant, and there seems to be no reason to justify its promotion. The greatest potential of Oryza barthii is probably as a source of resistance to various diseases affecting Oryza sativa.
Major references Burkill, H.M., 1994. The useful plants of West Tropical Africa. 2nd Edition. Volume 2, Families EI. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 636 pp. Hanelt, P. & Institute of Plant Genetics and Crop Plant Research (Editors), 2001. Mansfelds encyclopedia of agricultural and horticultural crops (except ornamentals). 1st English edition. Springer Verlag, Berlin, Germany. 3645 pp. Launert, E., 1971. Gramineae (Bambuseae - Pappophoreae). In: Fernandes, A., Launert, E. & Wild, H. (Editors). Flora Zambesiaca. Volume 10, part 1. Flora Zambesiaca Managing Committee, London, United Kingdom. 152 pp. National Research Council, 1996. Lost crops of Africa. Volume 1: grains. National Academy Press, Washington D.C., United States. 383 pp. Smith, C.W. & Dilday, R.H., 2003. Rice: origin, history, technology, and production. John Wiley & Sons, Hoboken, New Jersey, United States. 642 pp.
Other references Abo, M.E., Sy, A.A. & Alegbejo, M.D., 1998. Rice yellow mottle virus (RYMV) in Africa: evolution, distribution, economic significance on sustainable rice production and management strategies. Journal of Sustainable Agriculture 11(23): 85111. Akromah, R., 1987. Rice germplasm resources in Ghana. Plant Genetic Resources Newsletter 72: 4142. Clayton, W.D., 1970. Gramineae (part 1). In: Milne-Redhead, E. & Polhill, R.M. (Editors). Flora of Tropical East Africa. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. 176 pp. Clayton, W.D., 1972. Gramineae. In: Hepper, F.N. (Editor). Flora of West Tropical Africa. 2nd Edition. Volume 3, part 2. pp. 277574. Engels, J.M.M., Hawkes, J.G. & Worede, M. (Editors), 1991. Plant genetic resources of Ethiopia. Cambridge University Press, Cambridge, United Kingdom. 383 pp. Gibbs Russell, G.E., Watson, L., Koekemoer, M., Smook, L., Barker, N.P., Anderson, H.M. & Dallwitz, M.J., 1990. Grasses of Southern Africa: an identification manual with keys, descriptions, distributions, classification and automated identification and information retrieval from computerized data. Memoirs of the Botanical Survey of South Africa No 58. National Botanic Gardens / Botanical Research Institute, Pretoria, South Africa. 437 pp. Kaushal, P. & Ravi, 1998. Crossability of wild species of Oryza with Oryza sativa cvs PR 106 and Pusa Basmati 1 for transfer of bacterial leaf blight resistance through interspecific hybridization. Journal of Agricultural Science 130(4): 423430. Lu, B.R., 1999. Taxonomy of the genus Oryza (Poaceae): historical perspective and current status. International Rice Research Notes 24: 48. Phillips, S., 1995. Poaceae (Gramineae). In: Hedberg, I. & Edwards, S. (Editors). Flora of Ethiopia and Eritrea. Volume 7. Poaceae (Gramineae). The National Herbarium, Addis Ababa University, Addis Ababa, Ethiopia and Department of Systematic Botany, Uppsala University, Uppsala, Sweden. 420 pp. Vaughan, D.A. & Chang, T.-T., 1992. In situ conservation of rice genetic resources. Economic Botany 46(4): 368383.
Author(s)
| | M. Brink PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands |
Editors
| | M. Brink PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands | | | G. Belay Ethiopian Agricultural Research Organization, Debre Zeit Center, P.O. Box 32, Debre Zeit, Ethiopia |
Associate editors
| | J.M.J. de Wet Department of Crop Sciences, Urbana-Champaign, Turner Hall, 1102 South Goodwin Avenue, Urbana, IL 61801, United States | | | O.T. Edje Faculty of Agriculture, University of Swaziland, P.O. Luyengo, Luyengo, Swaziland | | | E. Westphal Ritzema Bosweg 13, 6706 BB Wageningen, Netherlands |
General editors
| | R.H.M.J. Lemmens PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands | | | L.P.A. Oyen PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands |
Photo editor
| | A. de Ruijter PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands |
Correct citation of this article: Brink, M., 2006. Oryza barthii A.Chev. In: Brink, M. & Belay, G. (Editors). PROTA 1: Cereals and pulses/Cιrιales et lιgumes secs. [CD-Rom]. PROTA, Wageningen, Netherlands.
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field of flowering plants
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