6. Saccharum officinarum Linnaeus, Sp. Pl. 1: 54. 1753.
甘蔗 gan zhe
Perennial, forming tall clumps. Culms 3–6 m tall, 2–5 cm in diam., 20–40-noded, solid, nodes glabrous, glabrous below inflorescence. Leaf sheaths glabrous, pilose at mouth; leaf blades 70–150 × 4–6 cm, usually glabrous, midrib large, white, margins sharply serrate, base rounded, apex acuminate; ligule 2–3 mm, ciliate. Panicle 50–100 cm, axis glabrous but pilose at nodes; racemes 10–25 cm; rachis internodes 3–6 mm, glabrous. Spikelets 3.5–4 mm; callus hairs 2–3 times length of spikelet; lower glume oblong, uniformly firm throughout, buff-colored, back glabrous, margins membranous and ciliate above, apex acuminate; lower lemma oblong-lanceolate, subequal to glumes; upper lemma linear, awnless. Lodicules glabrous. Anthers 3. Fl. and fr. autumn. 2n = 80.
Cultivated. Fujian, Guangdong, Guangxi, Hainan, Sichuan, Taiwan, Xizang, Yunnan [SE Asia, Pacific Islands; widely cultivated elsewhere].
This is the commercial crop sugarcane, now widely cultivated in tropical regions of the world. Most present-day cultivars contain genes from Saccharum spontaneum. Sugar is extracted from the soft, central tissue of the culm. The dyed inflorescence is used as an ornament.