紫穗稗 zi sui bai

Panicum esculentum A. Braun, Index Sem. Hort. Berol. 1861(App.): 3. 1861; Echinochloa frumentacea Link subsp. utilis (Ohwi & Yabuno) Tzvelev; E. utilis J. Ohwi & Yabuno.

Annual. Culms robust, erect, 1–1.5 m tall. Leaf sheaths smooth and glabrous; leaf blades linear, 20–50 × 1.2–2.5 cm, glabrous, margins thickened and wavy. Inflorescence erect, lanceolate, 10–30 cm, axis robust, scabrous along edges and with tubercle-based hairs; racemes 2–6 cm, robust, usually branched, closely spaced and overlapping. Spikelets purplish, tardily deciduous, plump, ovate or obovate-elliptic, 3.5–4 mm, hispid along veins with tubercle-based hairs; lower glume 1/3 as long as spikelet, acute; upper glume slightly shorter than spikelet; lower lemma herbaceous, sterile, acute or with a 0.5–2 cm awn; upper lemma 2.8–3.5 mm. Caryopsis long persistent, eventually falling. Fl. and fr. Aug–Oct. 2n = 54, 56, 72.

A crop plant. Guizhou, Hubei, Yunnan [cultivated in warm-temperate regions of Asia and Africa; introduced in America].

Echinochloa esculenta is cultivated both for grain and forage, like E. frumentacea, and the two are most easily distinguished by the color of the seeding heads. Echinochloa esculenta is thought to be a cultivated derivative of E. crusgalli that arose in China, Japan, and Korea.