GrassBase - The Online World Grass Flora

Descriptions

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

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

Pennisetum glaucum

HABIT Annual. Culms erect; robust; 150–300 cm long. Culm-nodes bearded. Ligule a fringe of hairs. Leaf-blades 50–100 cm long; 8–70 mm wide.

INFLORESCENCE Inflorescence a panicle. Peduncle pubescent above.

Panicle spiciform; linear, or elliptic, or ovate; 4–200 cm long; 0.8–5.5 cm wide. Primary panicle branches accrescent to a central axis; with lateral stumps on axis. Panicle axis terete; pubescent.

Spikelets subtended by an involucre. Fertile spikelets pedicelled; 1–9 in the cluster. Involucre composed of bristles; oblong; 2–7 mm long; base bluntly stipitate (1.1–25mm). Involucral bristles persistent; numerous; with an outer whorl of thinner bristles; inner bristles longer than outer; with longest bristle scarcely emergent, or with one conspicuously longer bristle; 12–26 mm long; terete; flexible; glabrous, or ciliate.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets obovate; dorsally compressed; 3–6 mm long; persistent on plant.

GLUMES Glumes one the lower absent or obscure; shorter than spikelet; thinner than fertile lemma. Upper glume oblong; 0.5–2 mm long; 0.15–0.33 length of spikelet; membranous; without keels; 0–3 -veined. Upper glume apex obtuse, or acute.

FLORETS Basal sterile florets male, or barren; with palea, or without significant palea. Lemma of lower sterile floret lanceolate, or oblong; 1.5–4.5 mm long; 0.5–0.75 length of spikelet; chartaceous; 5–7 -veined; ciliolate on margins; emarginate, or obtuse; muticous, or mucronate. Fertile lemma ovate; 1.4–4 mm long; coriaceous; without keel; 5–7(–9) -veined. Lemma margins flat; pubescent. Lemma apex emarginate, or obtuse. Palea coriaceous.

FLOWER Lodicules absent. Anthers 3; anther tip penicillate. Styles connate below.

FRUIT Caryopsis with adherent pericarp; obovoid; exposed between gaping lemma and palea at maturity; 2–5.5 mm long.

DISTRIBUTION Europe: eastern. Africa: north, west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, south, and western Indian ocean. Asia-temperate: western Asia, Arabia, and China. Asia-tropical: India and Indo-China. Australasia: Australia. South America: Caribbean.

NOTES Paniceae. Brunken.

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