Sorghum bicolor (L.) Moench

Family: Poaceae, Tribe: Andropogoneae


Pertinent Synonyms & Notes (particularly those used in California; go to GRIN for other synonyms)

includes ssp. bicolor and
nothossp. drummondii (Steud.) de Wet ex Davidse

Pertinent Common Names (particularly those used in California; go to GRIN for other common names)

shattercane, Sudan grass

Primary Disseminule Type

fertile spikelet, with or without 1–2 attached non-caryopsis-bearing spikelet(s)

Description (diagnostics are in brown)

Spikelets heteromorphic, occurring in pairs of 1 sessile fertile and 1 sterile or staminate spikelet or a triplet of 1 sessile fertile and 2 sterile or staminate spikelets in the terminal spikelet unit. Spikelets of cultivated taxa not disarticulating but separating via fracture, with disseminule consisting of a fertile spikelet, rachis fragment, and pedicel fragment. In uncultivated strains, disarticulation occurs at base of sessile floret and tip of pedicel of the sterile/staminate spikelet and disseminule usually consists of a fertile spikelet, rachis segment from beneath a sessile spikelet, and empty pedicel or pedicellate sterile/staminate spikelet.

Fertile spikelet sessile, variable in shape (typically broadly elliptic to ovate), dorsally compressed, (3)4–9(10) mm long, 2–4 mm wide, shiny, variable in color, consisting of one fertile floret and one basal sterile lemma.

Spikelet callus glabrous or pubescent.

Lower glume coriaceous, length of spikelet, its margins enclosing upper glume, 2-keeled near apex, apex obtuse or acute, surface glabrous or pubescent. Upper glume coriaceous, 1-keeled near apex, surface glabrous or pubescent.

Sterile lemma hyaline.

Fertile lemma hyaline, 1–5 mm long, apex entire or dentate, awnless or awn twisted, the column glabrous or pubescent.

Fertile palea absent or minute or present.

Sterile/staminate spikelet on pubescent pedicel, well-developed, glumes chartaceous.

Caryopsis reddish-brown or variable in color, 2.5–4.5 mm long x 1.5–2.5 mm wide, variable in shape (ovate to elliptic), dorsally compressed, exposed between gaping glumes at maturity (only ssp. bicolor), embryo 0.5–0.66 length of caryopsis.

Similar Species

Similar Species Comparison Chart

Risk Assessment (codes in yellow or red indicate cause for concern; assessments are current as of mid-2011; click AUQP, NZBORIC, or NZBPI for access to the most recent versions of these databases and possible assessment changes)

AUQP, NZBORIC, NZBPI