Poaceae
Oryza

Oryza officinalis Wall. ex Watt

First published in Dict. Econ. Prod. India 5: 501 (1891)
This species is accepted
The native range of this species is S. China to Tropical Asia and N. Australia. It is a perennial and grows primarily in the wet tropical biome.

Descriptions

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/177178/113899495

Conservation
LC - least concern
[IUCN]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: confident
[AERP]

Morphology General Habit
Perennial; caespitose. Culms geniculately ascending, or decumbent; robust; 120-150 cm long. Leaf-sheaths smooth; glabrous on surface. Leaf-sheath auricles absent. Ligule an eciliate membrane; 3-5 mm long; erose; obtuse. Leaf-blades 25-50 cm long; 10-20 mm wide. Leaf-blade surface scaberulous; rough on both sides. Leaf-blade margins scabrous.
Morphology Reproductive morphology Inflorescences
Inflorescence a panicle; comprising 6-20 fertile spikelets. Panicle open; ovate; 20-40 cm long. Primary panicle branches spreading, or drooping; 2-4 -nate; whorled at lower nodes; simple; 10-15 cm long. Panicle branches scaberulous. Spikelets solitary. Fertile spikelets pedicelled. Pedicels linear; angular; 0.5 length of fertile spikelet.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 2 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic, or ovate; laterally compressed; 4-5 mm long; 2-2.4 mm wide; falling entire.
Fertile
Spikelets comprising 2 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic, or ovate; laterally compressed; 4-5 mm long; 2-2.4 mm wide; falling entire.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes both absent or obscure.
Morphology Reproductive morphology Flowers Florets
Basal sterile florets similar; barren; without significant palea. Lemma of lower sterile floret lanceolate; 1.5 mm long; 0.3-0.4 length of spikelet; 1 -veined; without lateral veins; acuminate. Lemma of upper sterile floret lanceolate; 1.5 mm long; 1 length of lower sterile floret. Fertile lemma oblong, or orbicular; laterally compressed; 4-5 mm long; coriaceous; dark brown, or black; keeled; 5 -veined. Lemma midvein spinulose. Lemma surface scabrous and reticulate. Lemma margins interlocking with palea margins. Lemma apex awned; 1 -awned. Principal lemma awn 3-18 mm long overall. Palea elliptic; coriaceous; 3 -veined; 1-keeled. Palea keels spinulose. Palea surface scaberulous. Palea apex acute; awned; awns 1 mm long.
Morphology Reproductive morphology Flowers
Lodicules 2; membranous. Anthers 6; 2.5 mm long. Stigmas 2.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp. Disseminule comprising a spikelet.
Distribution
Asia-temperate: China. Asia-tropical: India, Indo-China, Malesia, and Papuasia. Australasia: Australia.
Reference
Oryzeae. Fl Ceyl.
Diagnostic
Panicle branches naked in lower half.
[GB]

Seed Collecting Guide. RBG Kew (2013-2016)

Morphology General Habit
Perrenial
Morphology Culms
Culms erect or creeping and rooting at lower nodes, 1.5-3 m tall, 7-10 mm in diam. Leaf sheaths more than 3 times internode length, auricles inconspicuous; leaf blades thick, 30-50 x 2-3 cm, abaxial surface and margins scabrous, adaxial surface scattered villous, midrib stout, lateral veins inconspicuous, base narrowed, puberulous, apex acuminate; ligule 1-4 mm
Morphology Reproductive morphology Inflorescences
Panicle loosely contracted, 30-50 cm, base often included in terminal sheath; branches 3-5 at loWest node, axils bearded, longest 10-25 cm, naked in lower half, apices of lowermost branches drooping
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets broadly ovate-oblong, 4-5 mm, length 1.5-2 times width, yellowish green or tinged brownish black, deciduous; sterile lemmas linear-lanceolate, 1.5-2 mm, apex acuminate; fertile lemma papillose, keel and marginal veins with hard glassy hairs; awn 5-10(-25) mm, slender, scabrid
Morphology Reproductive morphology Flowers Androecium Stamens Anthers
Anthers 1.5-2.5 mm
Morphology Reproductive morphology Fruits
Caryopsis reddish brown
Ecology
Low hills, alluvial plains, ditch banks. Altitude:0 - 1000 m
Distribution
China, Bhutan, Cambodia, India, Indonesia, Malaysia, Myanmar, Nepal, New Guinea, Philippines, Sri Lanka, Thailand, Vietnam.
Conservation
Least concerned
Phenology
Flower (July - March), fruit (July - March)
[SCG]

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/112680709/113899465

Conservation
VU - vulnerable
[IUCN]

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0

  • GrassBase - The Online World Grass Flora

    • Clayton, W.D., Vorontsova, M.S., Harman, K.T. and Williamson, H. (2006 onwards). GrassBase - The Online World Grass Flora.
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • IUCN Categories

    • IUCN Red List of Threatened Species
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2025. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2025. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Seed Collection Guides

    • Seed Collection Guides
    • http://creativecommons.org/licenses/by-nc-sa/3.0