Saccharum officinarum

HABIT Perennial; caespitose. Rhizomes absent. Culms erect; robust; 300–600 cm long; 20–45 mm diam. Culm-internodes solid; yellow, or mid-green, or purple; distally pruinose (below nodes). Leaf-sheaths loose. Ligule a ciliolate membrane. Leaf-blades linear, or lanceolate; 70–150 cm long; 30–60 mm wide; glaucous. Leaf-blade midrib conspicuous. Leaf-blade surface scaberulous; rough adaxially. Leaf-blade margins scaberulous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme. Peduncle glabrous, or pubescent above.

Panicle open; pyramidal; dense; 40–60 cm long. Primary panicle branches whorled at most nodes; 5–10 cm long. Panicle axis glabrous, or puberulous. Panicle branches glabrous, or puberulous; bearded in axils.

Racemes 5–10 cm long. Rhachis fragile at the nodes; subterete; glabrous on margins, or ciliate on margins. Rhachis internodes filiform; 4–7 mm long.

Spikelets in pairs. Fertile spikelets sessile and pedicelled; 2 in the cluster; subequal. Pedicels filiform; glabrous, or ciliate.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 3.5–4 mm long; falling entire; deciduous from the base, or with accessory branch structures. Spikelet callus bearded; base truncate. Spikelet callus hairs white; 7–12 mm long; 2–3 length of spikelet.

GLUMES Glumes similar; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; membranous; much thinner above; 2-keeled; 4 -veined. Lower glume surface flat. Lower glume apex acute. Upper glume lanceolate; 1 length of spikelet; membranous; much thinner above; without keels; 3 -veined. Upper glume margins eciliate, or ciliolate. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 1 length of spikelet; hyaline; 0 -veined; without midvein; without lateral veins; ciliate on margins; acute. Fertile lemma present, or absent; linear; 0–1 mm long; hyaline; 0 -veined. Palea absent or minute.

FLOWER Lodicules 2; cuneate; glabrous. Anthers 3; 1.5 mm long.

FRUIT Caryopsis with adherent pericarp; oblong; isodiametric; 1.5 mm long. Embryo 0.15 length of caryopsis.

DISTRIBUTION Europe: southwestern. Africa: north, Macaronesia, west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, south, and western Indian ocean. Asia-temperate: western Asia, Arabia, China, and eastern Asia. Asia-tropical: India, Indo-China, Malesia, and Papuasia. Australasia: Australia. Pacific: southwestern, south-central, northwestern, and north-central. North America: southeast USA and Mexico. South America: Mesoamericana, Caribbean, northern South America, western South America, Brazil, and southern South America.

NOTES Andropogoneae. Whalen 2003.

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