Sorghum propinquum

HABIT Perennial. Rhizomes elongated. Culms erect; 200–300 cm long. Culm-nodes pubescent. Ligule an eciliate membrane. Leaf-blades 30–100 cm long; 10–50 mm wide.

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme.

Panicle open; ovate; loose; 20–60 cm long. Primary panicle branches moderately divided. Panicle branches flexuous.

Racemes bearing few fertile spikelets; 2–6 fertile spikelets on each. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes filiform. Rhachis internode tip transverse; cupuliform.

Spikelets appressed; 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; comprising 2 subequal glumes without lemmas, or male; linear to lanceolate; dorsally compressed; 4–5.5 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; acute; muticous. Companion sterile spikelet lemmas when present 2; enclosed by glumes; muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; acute; 3.8–5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pubescent; base obtuse. Spikelet callus hairs white.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume ovate; 1 length of spikelet; coriaceous; much thinner above; pallid, or purple; without keels; keel-less except near apex. Lower glume surface pubescent. Lower glume apex entire, or dentate; 3 -fid; acute. Upper glume ovate; coriaceous; much thinner above; without keels. Upper glume surface pubescent. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; hyaline; 2 -veined; ciliate on margins; acute. Fertile lemma ovate; hyaline; 1 -veined. Lemma margins ciliate. Lemma apex dentate; 2 -fid; muticous. Palea absent or minute.

FLOWER Lodicules 2; oblong; fleshy; ciliate; hairy across the apex. Anthers 3. Stigmas 2; laterally exserted.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Asia-temperate: China and eastern Asia. Asia-tropical: India, Indo-China, Malesia, and Papuasia. Pacific: south-central and northwestern.

NOTES Andropogoneae. WDC.

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