Panicum antidotale Retz.

Global description

Panicum antidotale is a large rhizomatous vivacious herb, robust, with branched, lignified stems. It reaches 3 m in height. The knots are covered with woolly pubescence. The leaves are flat and elongated, glabrous above, often blue-green in color. They are provided with a membrano-ciliated ligule. The inflorescence is a large, broadly branched, oval, elliptical shaped panicle, up to 45 cm tall. The spikelets are divided into groups from the base to the end of the branches. Each spikelet is composed of 2 flowers of which only one is fertile. It is ovoid and contains a lanceolate ovoid grain.

General habit

Rhizomatous vivacious grass, very branched, 2.5 to 3 m tall.

Underground system

The roots are fibrous fasciculate and penetrate up to 45 cm deep in the soil, with thick, short, knotty rhizomes. The scales are densely pubescent.

Culm

The culm is 30 cm to 2 m tall or more. It is hard, often more or less woody at maturity, often creepy. Lateral branches are emitted at the nodes which gives the plant a diffuse appearance. Older plants that are often very branched look like bushes. The knots are usually swollen, glabrous or pubescent and woolly.

Leaf

The limb is flat. It is 15 to 30 cm long and 4 to 13 mm wide, with a glabrous upper surface. It is corded at the base and attenuated in tip at the top. It is often creepy. The sheath is open, glabrous, 4 to 8 cm long. The ligule is membrano-ciliate, with dense hairs 0.5 to 2.5 mm high.

Inflorescence

The inflorescence is a diffuse erect panicle with widely spread flexuous branches. It is oval to elliptical, 13 to 45 cm high. The primary branches are 5 to 15 cm long and more or less arranged in whorls at each node.

Spikelet

Spikelets are located at nodes, singly or in pairs. They are arranged in dense groups distributed from the base of the branches to their top. The spikelet has a pedicel 2.5 mm long. It is composed of 2 flowers of the same length, a sterile one at the base, the fertile one at the top. It falls don entirely. It is oval to elliptical, 2 to 3 mm long and 1 mm wide, more or less dorso-ventrally compressed, with marked ribs. The glumes and lemmas of the sterile flower are membranous. The lower glume is broad, acute to obtuse, smaller than the upper one, 1.5 to 2.5 mm long, one-third the length of the spikelet. It is traversed by 5 ribs. The upper glume and lemmas of the sterile flower are glabrous, blunt-ended, or abruptly short-billed. The lemma of the sterile flower is traversed by 7 veins. It presents a sharp summit. The 2 lemmas of this flower are about the same length. The lemma of the fertile flower is 2 mm long. It is hard, smooth, silky, flattened on the margin. It borders the palea tightly.

Grain

The ovoid lanceolate grain is 2 mm long.

Origin

Panicum antidotale is native to the Arabic peninsula,  India and West Asia.

Worldwide distribution

Species introduced to Africa, South America, Australia and Mauritius as a forage crop.

https://www.gbif.org/species/2705141