GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Oryza grandiglumis

HABIT Annual; caespitose. Rhizomes short. Butt sheaths papery; pallid. Culms erect; 200 cm long; 4–9 mm diam. Culm-nodes constricted; pallid, or brown. Leaf-sheaths narrower than blade at the collar; keeled; smooth; glabrous on surface. Leaf-sheath oral hairs ciliate. Leaf-sheath auricles falcate (small). Ligule an eciliate membrane; 4–6 mm long; entire (often split); truncate. Leaf-blades linear to lanceolate; 15–36 cm long; 1.5–4.5 mm wide. Leaf-blade surface scaberulous, or scabrous. Leaf-blade margins scabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle. Peduncle antrorsely scabrous above.

Panicle open; lanceolate, or elliptic; 15–40 cm long. Primary panicle branches ascending. Panicle branches angular; scabrous; hispid.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels linear; angular; scabrous; ciliate (short and stiff); tip cupuliform; bibracteate.

FERTILE SPIKELETS Spikelets comprising 2 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; laterally compressed; compressed strongly; rostrate; 7–9 mm long; 4–6 mm wide; falling entire. Spikelet callus glabrous; base truncate.

GLUMES Glumes both absent or obscure.

FLORETS Basal sterile florets similar; barren; without significant palea. Lemma of lower sterile floret lanceolate; 7–8 mm long; 1 length of spikelet; coriaceous; 1-keeled; 1 -veined; without lateral veins; hispidulous; awned. Awn of lower sterile floret 0.5–9 mm long. Lemma of upper sterile floret lanceolate; 7–8 mm long; 1 length of lower sterile floret; coriaceous; pubescent; ciliate on midvein; awned. Awn of upper sterile floret 0.5–9 mm long. Fertile lemma elliptic; laterally compressed; 6–8 mm long; coriaceous; keeled; 5 -veined. Lemma midvein spinulose. Lemma surface reticulate; hispidulous. Lemma margins involute. Lemma apex rostrate; awned; 1 -awned. Principal lemma awn 1–18 mm long overall. Palea elliptic; 1 length of lemma; indurate; thinner on margins (narrow hyaline margin); 3 -veined; 1-keeled. Palea keels scabrous. Palea surface scabrous. Palea apex acuminate.

FLOWER Lodicules 2; lanceolate; membranous. Anthers 6. Stigmas 2.

FRUIT Disseminule comprising a floret.

DISTRIBUTION South America: northern South America, western South America, and Brazil.

NOTES Oryzeae. TB.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.