Eleocharis dulcis (Burm.f.) Trinius ex Henschel
Family
Cyperaceae
Synonyms
Eleocharis plantaginea Roemer & Schultes, Eleocharis tuberosa Roemer & Schultes, Heleocharis plantaginoidea W.F. Wight.
Vernacular Names
| Malaysia | Tike. |
| English | Chinese water chestnut. |
| Indonesia | Teki (Indonesian), peperetan (Javanese), babawangan (Sundanese). |
| Philippines | Apulid (Tagalog, Bikol), pagappo (Ibanag), buslig (Bisaya,Ilokano). |
| Cambodia | Mëm phlông. |
| Thailand | Haeo (General), haeo-chin (Central). |
| Vietnam | M[ax] th[af]y, n[aw]n ng[oj]t, n[aw]ng. |
Geographical Distributions
Eleocharis dulcis is a widespread variable species of the Old World tropics, distributed from tropical West Africa and Madagascar through India eastwards to south-eastern China, Japan, Southeast Asia, northern Australia, Micronesia and Melanesia.
Description
E. dulcis is a perennial, rhizomatous, semi-aquatic herb that often grown as an annual crop. The rhizome is short with elongated stolons where each one is often terminates in a zoned, depressed spherical and brownish to blackish corm. It is 1-4 cm in diametre.
The stem is erect, cylindrical, tufted, measures 40-200 cm tall, measuring 3-10 mm in diametre, longitudinally striate and with distinctly transversely septate. The intersepta is 5-12 mm long, hollow, smooth and greyish to glossy dark green.
The leaves are reduced to some bladeless basal sheaths, measure 3-20 cm long, membranous, oblique or truncate at the apex and reddish brown to purple.
The inflorescence is a single, terminal, with many-flowered spikelet, cylindrical, measuring 1.5-6.0 cm x 3-6 cm, as thick as or somewhat thicker than the stem and obtuse to acute at the apex. The glumes are numerous, oblong, measuring 4.0-6.5 mm x 1.7-3.2 mm and with densely imbricate. The flowers are bisexual, with perianth of 6-8, slender, unequal and with white to brown bristles. There are 3 stamens with linear anthers and measure 2-3 mm long. The style is 7-8 mm long with 2-3-fid while the enlarged base persistent in fruit.
The fruit is an obovoid nut (achene), measuring 1.5-2.2 mm x 1.2-1.8 mm and shiny yellow to brown.
Ecology / Cultivation
E. dulcis occurs in open places both in salt or brackish and in freshwater swamps, often forming pure stands surrounding the open water, from sea level up to 1350 m altitude and as far as 40°N latitude in China. A long warm growing season with at least 220 frost-free days is needed for plant growth. The corms will only sprout at soil temperatures above 14°C. The field should be kept inundated for at least 6 months. The preferred soils are rich clay or muck soils with a pH of 6.9-7.3. E. dulcis can be grown successfully in slightly more acid soils provided that these are limed.
Line Drawing / Photograph
References
- Plant Resources of South-East Asia No. 9: Plants yielding non-seed carbohydrates.
