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.

Hordeum tetraploidum

HABIT Perennial; caespitose. Culms erect; slender; 10–50 cm long. Leaf-sheaths pubescent. Ligule an eciliate membrane; 0.5 mm long; truncate. Leaf-blades 1–4 mm wide. Leaf-blade surface glabrous, or puberulous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; bilateral; 2.5–6 cm long. Rhachis fragile at the nodes; flattened. Spikelet packing broadside to rhachis. Rhachis internodes oblong; 1–1.5 mm long; falling with spikelet above.

Spikelets in threes. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 2 in the cluster. Pedicels oblong.

STERILE SPIKELETS Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; dorsally compressed; 6–8 mm long; as long as fertile; deciduous with the fertile. Companion sterile spikelet glumes similar in width; subulate; 6–8 mm long. Companion sterile spikelet lemmas 1; 1.5–4.5 mm long; muticous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; dorsally compressed; 6–8 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes collateral; similar; shorter than spikelet, or reaching apex of florets; gaping. Lower glume subulate; 6–8 mm long; 1 length of upper glume; coriaceous. Upper glume subulate; 6–8 mm long; coriaceous.

FLORETS Fertile lemma lanceolate; 5–8 mm long; coriaceous; purple; shiny; without keel; 5 -veined. Lemma surface smooth. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn 2–4.5 mm long overall. Palea 5.5–6.5 mm long. Rhachilla extension 2.5–5 mm long.

FLOWER Lodicules 2; 1–1.5 mm long; ciliate; acute. Anthers 3. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; hairy at apex. Hilum linear.

DISTRIBUTION South America: southern South America.

NOTES Triticeae. Fl Pat 1995.

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