Sorghum versicolor

HABIT Annual, or perennial; short-lived. Culms erect; 25–250 cm long. Culm-nodes bearded. Leaves cauline. Ligule a ciliolate membrane; pilose on abaxial surface. Leaf-blades 10–30 cm long; 3–10 mm wide.

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme.

Panicle open; oblong; 5–25 cm long. Primary panicle branches whorled at most nodes; simple.

Racemes bearing 3–7 fertile spikelets on each. Rhachis fragile at the nodes; ciliate on margins. Rhachis hairs red; 2 mm long. Rhachis internodes filiform; 3.5–5 mm long. Rhachis internode tip transverse; cupuliform.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; ciliate.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; linear to lanceolate; 3–5 mm long; shorter than fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; muticous. Companion sterile spikelet lemmas enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic, or oblong; dorsally compressed; 5–7 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus bearded; base obtuse. Spikelet callus hairs white, or red.

GLUMES Glumes dissimilar; with lower wider than upper; exceeding apex of florets; firmer than fertile lemma; shiny. Lower glume ovate; 1 length of spikelet; coriaceous; dark brown, or black; without keels; keel-less except near apex. Lower glume surface glabrous, or pilose. Lower glume apex acute. Upper glume ovate; coriaceous; without keels. Upper glume surface glabrous, or pilose.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 0.8 length of spikelet; hyaline; 2 -veined; ciliolate on margins. Fertile lemma oblong; 3–5 mm long; hyaline; 1 -veined. Lemma margins ciliate. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 25–40 mm long overall; with twisted column. Column of lemma awn pubescent; hairy on the spiral. Palea absent or minute.

FLOWER Lodicules 2; ciliate.

DISTRIBUTION Africa: northeast tropical, east tropical, southern tropical, and south.

NOTES Andropogoneae. FTEA.

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