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.

Sorghum intrans

HABIT Annual. Culms erect; 100–360 cm long; 4–8 mm diam.; 4–6 -noded; without nodal roots, or with prop roots. Culm-nodes glabrous, or pubescent, or bearded. Leaves cauline. Ligule an eciliate membrane; 2–4 mm long; erose. Leaf-blades 10–15 mm wide. Leaf-blade surface hirsute; with tubercle-based hairs.

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme.

Panicle contracted; linear, or lanceolate; 14–40 cm long; 2.5–4 cm wide. Primary panicle branches 1–14 -nate; not whorled; simple; 2–5 cm long. Panicle branches scabrous; glabrous in axils, or bearded in axils; with prominent pulvini.

Racemes 1.5–3 cm long; bearing a triad of spikelets; bearing 1(–3) fertile spikelets on each. Rhachis fragile at the nodes; ciliate on margins. Rhachis hairs red; 1–1.6 mm long. Rhachis internodes linear; 5.5–6 mm long. Rhachis internode tip oblique.

Spikelets in threes. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 2 in the cluster. Pedicels filiform; straight, or curved (around sessile spikelet); 6–7 mm long; ciliate (rufously).

STERILE SPIKELETS Companion sterile spikelets well-developed; containing empty lemmas; linear; 9–24 mm long; as long as fertile; persistent. Companion sterile spikelet glumes chartaceous; 5 -veined; glabrous, or pubescent, or villous; entire, or dentate; muticous, or awned; several-awned (the lower 3-awned); with 0–15 mm long awn. Companion sterile spikelet lemmas enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; (6–)10–15(–20) mm long; falling entire; deciduous with accessory branch structures. Spikelet callus linear; 3–6 mm long; pubescent; base pungent; attached obliquely.

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; 2-keeled; keeled above; 9 -veined. Lower glume primary vein spinulose. Lower glume surface glabrous, or pubescent. Lower glume hairs dark brown. Lower glume apex rostrate. Upper glume ovate; coriaceous; without keels; 5–7 -veined. Upper glume surface glabrous, or pubescent. Upper glume muticous, or mucronate.

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; (4–)7.5–11(–15) mm long overall; with twisted column. Column of lemma awn glabrous, or pubescent; hairy on the spiral. Palea absent or minute.

FLOWER Lodicules 2; glabrous, or ciliate. Anthers 3; 3.6–5 mm long. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; oblong, or obovoid; 4–6.3 mm long; hairy at apex.

DISTRIBUTION Australasia: Australia.

NOTES Andropogoneae. Lazarides.

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