''Oryza punctata'' is an annual grass in the

rice Rice is a cereal grain and in its Domestication, domesticated form is the staple food of over half of the world's population, particularly in Asia and Africa. Rice is the seed of the grass species ''Oryza sativa'' (Asian rice)—or, much l ...

genus ''

Oryza ''Oryza'' is a genus of plants in the grass family. It includes the major food crop rice (species '' Oryza sativa'' and '' Oryza glaberrima''). Members of the genus grow as tall, wetland grasses, growing to tall; the genus includes both annua ...

'', also known as red rice, related to cultivated rice '' O. sativa''. ''O. punctata'' forms clumps or tussocks from 50–120 cm tall.Ibrahim, K.M. and Kabuye, C.H.S. (1987). An illustrated guide of Kenya Grasses. Food and Agriculture Organization of the United Nations. It is a native to tropical Africa and Madagascar but is also found in Thailand and other parts of Indochina.Fish, L., Mashau, A.C., Moeaha, M.J. and Nembudani, M.T. (2015) Identification guide to southern African grasses, An identification manual with keys, descriptions and distributions. Strelitzia ''O. punctata'' is a weed species in commercial rice growing operations although it appears to be rare in its native range.POWO (2019). "Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet

Retrieved 10 October 2019."Phillips, S., Namaganda, M and Lye, K.A. (2003) 115 Ugandan grasses. Makerere Herbarium Handbook series. Makerere University Herbarium (MHU), Department of Botany, Uganda.36, South African National Biodiversity Institute, Pretoria. ''O. punctata'' has an IUCN status of least concern.Phillips, J. and Yang, L. (2017). Oryza punctata. The IUCN Red List of Threatened Species 2017: e.T21347040A21413370. http://dx.doi.org/10.2305/IUCN.UK.2017-3.RLTS.T21347040A21413370.en. Downloaded on 10 October 2019. It is not generally eaten or used as fodder by farmers but there is some evidence that it has been used as such during periods of famine. Maria Vorontsova (botanist), Vorontsova, M.S., Dransfield, S., Renvoize, S., Besnard, G., McRobb, A., Razanatsoa, J., Prisca, N.O., Rakotoarisoa, S.E., Ralimanana. (2018). Identification guide to the Grasses and Bamboos in Madagascar. Kew Publishing. Due to the importance of the crop varieties of rice (''Oryza. sativa'' and ''O. glaberrima'') globally, the evolution of the ''Oryza'' genus as a whole has been studied extensively.Elert, E. (2014) Rice by the numbers: A good grain. Nature. 514(S50-51). A lot of information about ''O. punctata'' has been elucidated as a secondary benefit to this commercial research. ''O. punctata'' evolved some 5 million years ago in the second of two rapid radiation events that occurred in the ''Oryza'' L. genus.Zou, X.H., Zhang, F.M., Zhang, J.G., Zang, L.L., Tang, L., Wang, T. and Ge, S. (2008). Analysis of 142 genes resolves the rapid diversification of the rice genus. Genome, Biology. 9(R49).

Description

''Oryza punctata'' is a caespitose (tussock forming) annual

hydrophyte Aquatic plants, also referred to as hydrophytes, are vascular plants and non-vascular plants that have adapted to live in aquatic environments ( saltwater or freshwater). In lakes, rivers and wetlands, aquatic vegetations provide cover for aquat ...

(grows in/on water).Flora Zambesiaca accessed on 10 October 2019 http://apps.kew.org/efloras/namedetail.do?qry=namelist&flora=fz&taxon=7908&nameid=20229 The culm base of ''O. punctata'' is spongy and greater than 4 mm in diameter. The culm is

glabrous Glabrousness () is the technical term for a lack of hair, down, setae, trichomes, or other such covering. A glabrous surface may be a natural characteristic of all or part of a plant or animal, or be due to loss because of a physical condition, ...

(smooth and without hairs) and striate (parallel longitudinal grooves); it is erect or geniculately (bent like a knee) ascending and from 50–120 cm tall with 3–5 nodes.Harker, K.W. and Napper, D. (1960) An Illustrated Guide to the Grasses of Uganda. The leaf sheath is scarious, often spongy, aerenchymous (spongy tissue that forms spaces of air channels), distinctly striate, it can be loose and often slips away from stem, rounded or slightly keeled towards the upper section, auricled at the mouth, smooth and glabrous. Leaf lamina are between 15–45 cm and 0.5–2.5 cm in length and width respectively, they are linear or narrowly elliptic, acuminate, broadest in the middle, pale green or rarely glaucous, slightly flaccid, expanded or folded at the midrib, asperulous (slightly rough), has a distinct midrib visible beneath. Ligules are mostly greater than 4 mm in length and up to 8 mm; they are soft, rounded, truncate or somewhat acute, whitish and often split along their longitudinal axis when dried; ligules are occasionally lacerate/ glabrous.Tateoka, T. (1965) A Taxonomic Study of Oryza eichingeri and O. Punctata. Bot. Mag. Tokyo. 78, 156–163. Flowering occurs from November to April. Inflorescence

panicle In botany, a panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a p ...

s branch structure is spreading, 15–35 × 3–17 cm, solitary or occasionally adnate; narrow to widely elliptic or occasionally fan shaped. These panicles are erect or drooping slightly, rachides obtusely angular; glabrous or inconspicuously scaberulous,

pedicels In botany, a pedicel is a stem that attaches a single flower to the inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branch ...

2–5 mm in length.

Spikelet A spikelet, in botany, describes the typical arrangement of the inflorescences of grasses, sedges and some other monocots. Each spikelet has one or more florets. The spikelets are further grouped into panicles or spikes. The part of the sp ...

length and width are between 4.9–6.5 mm and 1.9–2.6 mm respectively (length is usually 2.5x width). Spikelets are transversely attached to the pedicel, they are asymmetrically elliptic to oblong or broadly oblong viewed laterally, glaucous/ greyish-green. Intermediate forms have been observed where it can be difficult to distinguish between ''O. punctata'' and ''O. eichingeri''.

Glume In botany, a glume is a bract (leaf-like structure) below a spikelet in the inflorescence (flower cluster) of grass Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flow ...

s are much reduced to a thin whitish rim. Sterile lemmas are about equal in dimensions, 1–1.5 mm in length, glabrous, acute and triangular. Fertile lemmas are just shorter than the spikelet; they are semi-elliptic-oblong when viewed laterally, coriaceous; flanks are finely tesselate, shortly but stiffly hispid or rarely glabrous, keel and margins are ciliate, lateral apical protrusions almost always distinct. ''O. punctata'' awns are pale yellow, have rigid bristles which are straight or flexuous and commonly exceed 3 cm (2–7.5 cm) in length. Palea are shorter and thinner than the lemma, apex acute or tapering into a point.

Anthers The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filamen ...

are 1.3–1.5 mm long and oblong shaped with a pale violet colour. Botanically, the fruits of rice plants are known as caryopses, which here are 4–4.75 mm × 1.5–1.75 mm in length and width respectively; they are oblong, glabrous and pale brown.

Etymology

The common name for ''Oryza punctata'' Kotschy ex Steud. is Red rice. Oryza is a noun meaning rice in Late Latin (orȳza), it has origins in Ancient Greek (órūza) which lent from an Eastern Iranian language.Lewis, C.T., and Short, C. (1879). A Latin Dictionary, Oxford: Clarendon Press. Punctata means pointed or punctuated in Latin. The former most likely applies to this species. The

synonym A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...

''Oryza Schweinfurthiana'' Prodoehl. was published in Bot. Arch. (1922) but is not accepted.Botanisches Archiv. Zeitschrift für die gesamte Botanik. Königsberg and Dahlem bei Berlin. https://www.ipni.org/p/1652-2

Habitat and ecology

''Oryza punctata'' grows in rock-pools, permanent pools near rain forest and swampy soils near streams. ''O. punctata'' is a pest plant in commercial rice cultivation in Eswatini. The plant itself is of no use for grazing although there is some recorded use of the species for food in Kenya.Vaughan, D.A. (1994) The wild relatives of rice: a genetic resource handbook. International Rice Research Institute, Manila, Philippines ''O. punctata'' is one of two wild rice species that can be found in Madagascar. It only produces a small number of seeds and so if it is eaten at all, it is usually during a period of desperation such as a

famine A famine is a widespread scarcity of food caused by several possible factors, including, but not limited to war, natural disasters, crop failure, widespread poverty, an Financial crisis, economic catastrophe or government policies. This phenom ...

Distribution

''Oryza punctata'' is distributed across tropical Africa and Madagascar as well as Thailand and other parts of Indo-China. In terms of altitude, ''O. punctata'' can be found between 33 and 1230m above sea level. ''O. punctata'' has a large geographic distribution. It is native to Angola, Benin, Cameroon, Central African Republic, Chad, Congo, Côte d'Ivoire, Democratic Republic of the Congo, Eswatini, Ethiopia, Ghana, Kenya, Madagascar, Malawi, Mozambique, Nigeria, South Africa, Sudan, Tanzania, Togo, Uganda, Zambia and Zimbabwe.Darbyshire, I., Kordofani, M., Farag, I., Candiga, R. & Pickering, H. (eds.) (2015). The Plants of Sudan and South Sudan: 1-400. Kew publishing, Royal Botanic Gardens, Kew.

Taxonomy and systematics

''Oryza punctata'' is one of over 300,000

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

species. ''O. punctata'' is in the Poaceae family (Grasses) belonging to a large clade known as the

Monocotyledon Monocotyledons (), commonly referred to as monocots, ( Lilianae '' sensu'' Chase & Reveal) are flowering plants whose seeds contain only one embryonic leaf, or cotyledon. A monocot taxon has been in use for several decades, but with various ranks ...

(Monocots), which consists of 93 families. Monocots are characterised by a single cotyledon, parallel leaf venation and scattered vascular bundles.Willis, K.J. and McElwain, J.C. (2014). The Evolution of Plants. (2nd Edn). Oxford University Press, UK. 181-183pp. Earliest evidence of Monocots is based on fossil pollen and dates back to the early

Aptian The Aptian is an age (geology), age in the geologic timescale or a stage (stratigraphy), stage in the stratigraphic column. It is a subdivision of the Early Cretaceous, Early or Lower Cretaceous epoch (geology), Epoch or series (stratigraphy), S ...

some 117mya as read in. Earliest grass pollen and flower fossils date back to approximately 60-55mya but Poaceae only became dominant over many other plants groups about 24 mya; this is thought to be due to cooling and drying of the environment.Kellogg, E.A. (2000). The grasses: a case study in macroevolution. Annu. Rev. Biosystem. Ecol. 31, 217-238.Chapman, G.P, (1996). The Biology of Grasses. Cambridge University Press, UK, 273p. The genus ''Oryza'' L. (Rice) diverged from the rest of Poaceae (Grasses) relatively recently, approximately 14 mya.Tang, L., Zou, X.H., Achoundong, G., Potgeiter, C., Second, G., Zhang, D.Y., Ge, S. (2010). Phylogeny and biogeography of the rice tribe (Oryzeae): Evidence from combined analysis of 20 chloroplast fragments. Molecular Phylogenetics and Evolution. 54, 266-277. ''Oryza'' L. originated in Asia and began to diversify, spreading to Australia, America and Africa in 3, 1 and 4 separate dispersal events respectively. ''Oryza'' L. has experienced two rapid radiation periods: the first event happened about 10 mya and the second - more recent - took place 5 mya. These two rapid radiation periods can account for the majority of diversity within the genus, the second of which lead to the emergence of ''Oryza punctata''. Additional research is needed to investigate relationship between these radiation events and geographic dispersal events. Rice (''Oryza'' L.) has been widely studied in

systematics Systematics is the study of the diversification of living forms, both past and present, and the relationships among living things through time. Relationships are visualized as evolutionary trees (synonyms: phylogenetic trees, phylogenies). Phy ...

and many other disciplines due to its agricultural importance, making up 19% of the calories consumed worldwide every day. A taxonomic description of ''Oryza punctata'' has been provided above.Hutchinson, J., Dalzeil, J.M., Keay R.W.J., Hepper, N. (2014) Flora of West Tropical Africa (2nd edn) Crown Agents for Overseas Publishing and Administrations, Millbank, London, S. W. 1. With global populations set to reach 10 billion by 2050, it is essential to improve key crops species such as rice. Systematics can help play a role in identifying wild crop relatives and investigating them for useful genetic adaptations. While ''O. punctata'' may itself be a pest species in paddy fields, wild rice species are seen as a valuable source of useful genes which can be carried over into agricultural species. Resistance to brown planthopper (BPH) and Zigzag leafhopper (ZLH) have been seen in ''O. punctata'', which infests commercial rice plants.Jena, K.K. (2010). The species of the genus Oryza and transfer of useful genes from wild species into cultivated rice, O. sativa . Breeding Science: 518-523.

Status

''Oryza punctata'' L. is listed as a species of

least concern A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wil ...

according to th
International Union for Conservation of Nature
(IUCN). This means the species has been assessed and is not a focus for species conservation. However, ''O. punctata'' has been cited as a rare species in some parts of native range such as Uganda, or stated that it had a rare frequency in southern Africa.

References

{{- punctata Grasses of Africa Flora of West Tropical Africa Flora of West-Central Tropical Africa Flora of Northeast Tropical Africa Flora of East Tropical Africa Flora of South Tropical Africa Flora of Southern Africa Flora of the Western Indian Ocean