Nut Grass

Overview

Nut grass is thought originated from Africa, now it is widely distributed throughout the warmer parts of the world and it is very common allover South-East Asia. As one of the world's worst weeds in cultivated areas such as lowland rice, maize, sugar cane and vegetables.

Vernacular Names

Purple Nutsedge (English), Teki (Indonesian), Hamasuge (Japanese), Rumput haliya hitan (Malaysia), Monhnyin-bin (Myanmar), Mutha (Tagalog-Philippines), Haew moo (Thailand), Xiang fu zi (Chinese).

Agroecology

C. rotundus is widespread in the tropics and subtropics, growing in almost every soil type, altitude, humidity, soil moisture and pH, but not in soils with a high salt content. Its range at increasing latitudes and altitudes is limited by cold temperatures. It occurs in cultivated fields, fallow land, neglected areas, road and rail sides, banks of irrigation canals and streams, edges of woods and sand dunes. Generally, it does not tolerate shade.

Morphology

• Roots - fibrous roots.
• Rhizomes - slender, initially white and fleshy with scaly leave and become fibrous, wiry, and very dark brown with age.
• Tuber - subglobose or ellipsoid, 0.5-2.5 cm long.
• Stem - slender, 15-30(-75) cm long.
• Leaves - 10 to 30 cm long, 2-6 mm wide, and narrowly linear.
• Flowers - bisexual each with three stamens and a pistil bearing three stigmas.
• Fruits - an achene, obovoid or oblong, brown to black, 3-angled, one-seeded, covered with a scurfy bloom.

Cultivation

• Most C. rotundus cultivated by tubers.
• Propagated by seeds and rhizomes. Most seeds of C. rotundus are not viable; germination seldom averages more than 1-5%.

Chemical Constituents

Flavonoids, terpenoids, sesquiterpenes, tannins, saponins, alkaloids, essential oil, glycosides, steroids, cyprotene, acopaene, cyperene, aselinene, rotundene, valencene, cyperol, gurjunene, trans-calamenene, dcadinene, gcallacorene, cadalene, cypertundone, amuurolene, gmuurolene, cyperotundone, mustakone, isocyperol, acyperone, 4,11-selinnadien-3-one, and 1,8-cineole.

Traditional Medicinal Uses

• Considered anti-arthritic, alternative, astringent, carminative, contraceptive, demulcent, emmenagogue, emollient, febrifuge, immunostimulant, laxative, stimulative, tonic, vermifuge.
• Studies have suggested antidiabetic, antioxidant, cytoprotective, wound healing, antihypertensive, antimicrobial, anti-obesity, anticandidal, anti-inflammatory, antimutgenic, analgesic, cytotoxic, antidiarrheal, anticonvulsant, lipid lowering, nootropic, neuroprotective, anti-amoebic, anticholinesterase, antigiardial, antispasmodic, antidepressant properties.
• In South-East Asia, the most widespread medicinal applications of the tubers are against hepatic disorders, as an emmenagogue and for post-partum treatment, as  a stomachic, as a febrifuge, against renal and urologic disorders, and to treat ulcers.
• In the Philippines, it is used for dysentery.
• For skin diseases, a warm decoction is used to wash the affected areas.
• In India, it is used for wound healing. Roots used medicinally as a diaphoretic, astringent, stimulant, tonic, diuretic and demulcent. Also used as vermifuge and emmenagogue.
• In China, tubers are used as tonic, stimulant, and stomachic.
• Fresh tubers are applied to breast as paste or warm plaster as a galactagogue. Dried tubers are used for spreading ulcers.