Oryza barthii A.Chev.

Global description

Oryza barthii is an erect grass. The leaves are long and tapered, narrowed at the level of the ligule and glabrous. The ligule is very long and membranous, with a truncated apex. The inflorescence is an erect dense panicle. The spikelets are solitary, briefly pedicelled and include 3 flowers including 2 sterile. The glumes are very small. The lower lemmas are sterile. The upper lemma and palea are 9 to 11 mm long, leathery and strongly scabrous. The lemma is surmounted by an awn of more than 10 cm and scabre. The grain remains included in the lemma and palea.

First leaves

The first leaves have a rolled prefoliation. The blade is linear, 3 to 10 cm long for the first 3 leaves and 5 to 8 mm wide. The base is narrowed, the apex is sharp tapered. The margin is smooth to finely scabrous. The blade is erect obliquely and glabrous. The main nerve is not very marked. The ligule is very tall and membranous with a rounded truncated apex. The sheath is cylindrical and sometimes provided with auricles at the level of the ligule. It is totally hairless.

General habit

Oryza barthii is erect. The individuals are isolated or have low tillering. This species is up to 1.5 m tall.

Underground system

The roots are fasciculate.

Culm

The culm is cylindrical, 3 to 5 mm wide. It is hairless. The knots are dark in color.

Leaf

The leaves are alternate, distributed throughout the culm. The sheath is cylindrical and weakly keeled. It is totally hairless and has a white papery margin. The ligule is membranous, with rounded truncated apex and 2 to 8 mm high. The lamina is linear, with a narrowed base and a long pointed apex. It is 20 to 50 cm long and 10 to 15 mm wide. It is totally hairless. The main vein is not very marked. The margin is smooth to finely scabrous.

Inflorescence

The inflorescence is a dense panicle, ellipsoidal in shape, 15 to 30 cm long and 7 to 10 cm wide. The branches of the panicle are erect. Each carries 8 to 15 solitary spikelets carried by a short pedicel of 2 mm.

Spikelet

The spikelets are oblong, 9 to 11 mm long and 3 mm wide and strongly scabrous. They are composed of 3 flowers, 2 of which are sterile including only the lemma. The glumes are reduced to small, slightly visible membranous sections at the base of the spikelet. The lemmas of the sterile flowers are lanceolate, 2.5 to 4 mm long and finely scabrous. The lemma of the fertile flower is elliptical, strongly compressed, 8-10 mm long and 3 mm wide. It is leathery, surmounted by a long edge of 10 to 17 cm and usually tinged with pink or purple. The lemma and the ridge are strongly scabrous. The palea is as long as the lemma but much narrower. Its summit is sometimes surmounted by a very short edge less than 1 mm long. She is highly scabrous. Spikelets are quickly sessile and fall as they mature.

Grain

The grain remains locked in the lemma and palea. It is oblong, and 6 to 8 mm long. The tegument is smooth, light brown in color.

https://www.gbif.org/species/2703457