Sp. Pl. 1, 333 (1753); FWTA: 365 (1972); Gen. Gram.: 71 (1986).- Tyep-species: Oryza sativa L.
Description:
* Erect annuals or perennials. Leaves flat, with membranous ligule.
* Panicle open or rather dense; branches numerous, racemose with shortly pedicelled spikelets.
* Spikelets 3-flowered with one fertile floret and 2 sterile lemmas, strongly laterally compressed, falling entire from the pedicel. Glumes absent or represented by obscure lips at the pedicel-tip. Both lower florets represented only by narrow lemmas, these usually subulate or linear and much shorter than the spikelet; upper floret fertile; lemma coriaceous, strongly keeled, prominently 5-nerved, with or without an awn; palea similar but narrower, keeled.
Genus with about 20 species of humid forests and swamps. O. sativa (rice) is cultivated throughoutthe tropics and subtropics.