Chrysopogon zizanioides (L.) Roberty

Last updated: 29 August 2016

Scientific Name

Chrysopogon zizanioides (L.) Roberty

Synonyms

Agrostis verticillata Lam. [Illegitimate], Anatherum muricatum (Retz.) P.Beauv., Anatherum zizanioides (L.) Hitchc. & Chase, Andropogon aromaticus Roxb. ex Schult. [Invalid] Andropogon muricatum Retz. [Spelling variant], Andropogon muricatus Retz. Andropogon nardus Blanco [Illegitimate], Andropogon odoratus Steud.[Invalid], Andropogon zizanioides (L.) Urb, Chamaeraphis muricata (Retz.) Merr, Holcus zizanioides (L.) Stuck.Oplismenus abortivus Roem. & Schult. [Invalid]Phalaris zizanioides L, Rhaphis muricata (Retz.) Steud. [Invalid], Rhaphis zizanioides (L.)Roberty, Sorghum zizanioides (L.) Kuntze, Vetiveria arundinacea Griseb., Vetiveria muricata (Retz.) Griseb, Vetiveria odorata Virey, Vetiveria odoratissima Lem.-Lis., Vetiveria zizanioides (L.) Nash [1]

Vernacular Name

Malaysia Nara wastu, akar wangi, kusu-kusu. [2]
English Vetiver (grass), khus, khus-khus [2]
Indonesia Akar wangi (general) ), larasetu (Javanese), usar (Sundanese).[2]
Thailand Faek, ya-faekhom, ya-faeklum.[2]
Philippines Philippines: moras (Tagalog), amora (Cebu), anis de moro (Ilokano). [2]
Vietnam c[of] h[uw][ow]ng b[af]i, h[uw][ow]ng b[af]I [2]
France Vétyver, chiendent odorant [2]

Geographical Distributions

Chrysopogon zizanioides grows naturally in swamp areas of northern India, Bangladesh, Burma (Myanmar) and occurs probably naturalized in many parts of South-East Asia. It has been in cultivation in India for centuries and is now found throughout the tropics and in many subtropical areas. It is grown for its oil mainly in Haiti, West Java, India, Réunion, China and Brazil. To a very limited extent it is grown commercially as far north as Texas. The use of vetiver in erosion control spread first from India to the Caribbean and Fiji and later to many tropical areas, including all countries of South-East Asia. [2]

Botanical Description

C. zizaniodes belongs to the genus Gramineae. Coarse, perennial grass forming large, dense clumps with a stout, compact, aromatic, branched, spongy rhizome and fibrous root system up to a depth of 4 m. Culm erect, 1—1.5(—3) m tall, 2—8 mm in diameter, terete, solid, glabrous. [2]

The leaf sheaths laterally compressed, 10—20 cm long, keeled; ligule a very shallow fimbriate rim, 0.3—1.7 mm long; blade linear, flat or folded, stiff, 30—75(—90) cm x 4—10(—15) mm, glabrous below, puberulent in lower upper side, scabrous along the edges and back of the midrib. [2]

The inflorescence is a well-exserted, panicle terminal, measures 15-40 cm long, with 6-10 whorls of up to 20 slen­der bracts while the articulating racemes are up to 10 cm long. The intern­odes of the racemes and pedicels are slender and slightly thickened apically. The internode of spikelets bear slender rachis which is 5-6 mm long, hairless or with short scattered hairs. The spikelets are in pairs, 1-sessile and 1-pedicelled, 2-flowered and the pair falls as a unit. The sessile spikelet is 3.5-5.5 mm long, with well-developed, pointed, hairless or pubescent callus, with barren lower floret and perfect upper floret. The glumes are chartaceous and bear papillose-based spicules or stiff hairs. The lower glume is lance-shaped, folded about the mid-vein, as long as the spikelet and 7-veined. The upper glume is equal to or slightly shorter than the lower glume. It is 3-veined. The lower floret is with hya­line, ciliate lemma and without palea, while the upper floret is with lance-shaped lemma, measures 3-4 mm long, 1-3-veined, with a short scabrid awn and oblong palea, measures 1.5-2.5 mm long, delicately hyaline, 1-veined and spinulose ­hairy at the tip. The 3 stamens are with orange anthers about 2 mm long. The pistil is with a hairless ovary and 2 plumose and purple stigmas. There are 2 lodicules which are free and fleshy.

The caryopsis is rarely formed, oblongoid to spindle-shaped and slightly oblique at apex. The pedicelled spikelet is more slender and measures 2.5-4.5 mm long. The lower glume is 3-7-veined while the upper glume is 3-veined. Both florets are staminate or with rudimentary stamens, of which anthers are up to 2.5 mm long.

Cultivation

Soil Suitability and Climate Requirement

C. zizanioides is a hydrophyte, often dominant in fresh-water swamps, floodplains and on stream banks. It can only survive and spread naturally in swampy areas. It also exhibits, however, xerophytic properties and grows remarkably well under alternating very wet and very dry conditions with annual rainfall ranging from (300—)1000—2000(—3000) mm. Frost is not generally tolerated, but a few selections survive frequent frosts, with extremes as low as —9°C. The average maximum temperature required for good growth is 25°—35°C; absolute maxima may be about 45°C. It should not be shaded permanently, although healthy hedges of vetiver can be maintained in sugar-cane plantations, as the plants recover quickly after the harvest of the cane.

Field Preparation

Land Preparation

C. zizanioides is tolerant of very poor and adverse soil conditions. It is grown on heavy clays and on leached, poor sands. Soil reaction may range from very acid (pH 4.0) to very alkaline (pH 9.6). Mature plants are tolerant of saline soil; yield reductions of 50% (comparable to those of cotton and barley) have been found where salinity in the top 50 cm of the soil was 15—24 mS/cm. It can survive fire, rough trampling and grazing. For the production of vetiver oil, light sandy soils are required to facilitate harvesting of the smaller roots, which contain most oil. [2]

Production of Planting Materials

 C. zizanioides is propagated vegetatively by dividing clumps into splits consisting of one or a few shoots of 15—20 cm long with a portion of the roots. When large numbers of plants are needed, mother plants are heavily fertilized to promote tillering. Although it is cheaper to plant splits directly in the field, the use of splits allowed to regenerate roots in mist frames or raised in containers ensures maximum survival and fast establishment. When no containers are used, nurseries should be in light soil so that plants can be pulled up easily. Culms can also be used to produce large numbers of new shoots for propagation. They are cut, placed in a nursery on damp sand and lightly covered, keeping them under mist. Slitting the leaf sheath improves the success rate. After 2 months most nodes have produced roots and start forming leaves. Plant regeneration through somatic embryogenesis of callus in vitro is possible and plantlets from a tissue-cultured clone from Mauritius are available commercially. For oil production, splits are planted in well prepared soil, in rows spaced 50—60 cm apart and at 20—30 cm between plants. They are sometimes planted on ridges or on 2-row beds. Planting is done at the onset of the rainy season. To make contour hedges, a spacing of 20 cm between plants is used. [2]

Field maintenance

Fertilisation

 C. zizanioides is tolerant of many herbicides, except those based on glyphosate. For good growth the use of manure or chemical fertilizer at a rate of 80 kg N and 30 kg each of P2O5 and K2O is recommended. The N fertilizer should be applied in 3 equal doses, at planting, ridging and at about 8 months after planting. Intercropping with short-duration pulses can be done during the early stages of growth. Intercropping in coconut and areca palm plantations having a relatively open canopy is sometimes practised. Irrigation is sometimes economic. For erosion-control hedges it is essential to fill gaps between plants. When required, plants can be removed simply by cutting them off below the rhizome with a shovel, hoe or plough. [2]

Weed Control

Two months after field planting of vetiver, the soil is earthed-up into ridges 30 cm wide and 20 cm high. To establish vetiver, early weeding is important. Weeding is done 3—4 times in the first year and a few times in the second. The final weeding is done just before harvesting to avoid roots of weeds in the harvested vetiver roots. [2]

Pest and Disease Control

C. zizanioides has few disease and pest problems. Curvularia trifolii leaf blight may cause damage during the rainy season; it causes the leaves to turn pale-yellow and to eventually dry out. Fusarium spp. are also reported to cause damage. A number of parasitic fungi have been identified in Malaysia, which grow on vetiver without causing much damage. They may, however, become troublesome when susceptible crops are grown with vetiver. These fungi include Curvularia lunata and C. maculans, causing leaf spot in oil palm, and a number of Helminthosporium spp. causing leaf spot or blight in oil palm, coconut palm, maize and sugar cane. Larvae of Chilo moths are the most serious pest of vetiver and crops grown in association with it. The larvae feed on the fibrovascular bundles, resulting in wilting of the affected stems and leaves. They can possibly be controlled by burning. Other reported pests are white grubs (Eupladia spp.) and rats. Under dry conditions, termites attack dead leaf and stem material, causing the centre of clumps to die. In extreme cases, plants are even killed. Resistance to some root-knot nematodes is effective. In trials in Brazil, vetiver was not affected by Meloidogyne incognita race 1 and Meloidogyne javanica. [2]

Harvesting

Roots and rhizomes of vetiver are harvested 15—18 months after planting when their essential oil content is highest. In Java harvesting is sometimes done already after 12 months, elsewhere it is sometimes postponed until after 24 months, which results in lower yields, but higher quality oil, being heavier and darker coloured. A light irrigation is sometimes given prior to harvesting, to make it easier to digg up the roots manually. The use of a single-disk plough digging to 40 cm depth has been time efficient and effective in trials. On sloping land, harvesting can cause serious erosion. [2]

Postharvest handling

The harvested roots of vetiver are cleaned of adhering earth by washing in running water and drying in the field for a few days; they are then separated and allowed to dry in the shade to 10—15% moisture content. Vetiver oil is obtained by steam distillation of fresh or stored roots; storing the roots for about 6 months has been reported to improve oil quality. Chopped roots are soaked in water for 10—20 hours to render them soft before being put into stills. The duration of distillation varies from place to place, depending on the provenance and age of the roots, and the quantity loaded. In southern India, a load of 125 kg is distilled for 72—96 hours. In Java, the process normally takes 12—36 hours, in Reunion 36—48 hours. The first fraction of the oil distilled over is lighter than water, the later fraction heavier. The fractions are collected in separating tanks, eventually combined and filtered warm in steam-jacketed filters or centrifuged to free the oil from water. A small amount of salt may be added to the roots to increase the recovery of the oil fraction heavier than water. A portion of the oil is water-soluble. To recover this fraction, distillation water is collected from the separators and re-used in the distillation still. The quality of the oil improves with storage, because it converts the harsh 'green' earthy note of freshly distilled oil to a fuller, heavier and sweeter odour.

Chemical Constituent

C. zizaniodes has been reported to contain sesqiterpenes(3-4%), sesquiterpenols (18-25%), sesquiterpenones (7-8%), beta-vetivenene, beta-vetivone, alpha-vetivone. [3][4]

Plant Part Used

Roots [2]

Traditional Use

From the rhizome and roots of vetiver an essential oil, vetiver oil, is steam-distilled, which is used in perfumes, deodorants, soaps and other toilet articles. Its scent is heavy and woody. In perfumery, the essential oil and vetiveryl acetate, synthesized by acetylation of vetiver oil, are important fixatives for more volatile fragrance materials. The chemical stability of vetiver oil under alkaline conditions makes it a suitable scent compound for soaps. In certain canned foods e.g. asparagus and peas, fractions of vetiver oil are used to reinforce the natural odour and taste. [2]

Young leaves of C. zizanioides are eaten by cattle and goats, though older clumps are left alone when other fodder is available. Stems and old leaves are an excellent, long lasting thatch and can be processed into a coarse paper-pulp. [2]

The roots are used for making mats, fans or 'pamaypay' in the Philippines and cooling screens named 'tatties' in India. These give a pleasant smell to a room, especially when dampened. Dried roots or sachets of powdered roots are stored between clothes to give them a pleasant smell and to repel insects. Vetiver oil and roots have insecticidal and insect-repellant properties. Nootkatone, derived from vetiver essential oil, has been shown to be a strong insecticide and repellant against Coptotermes formosanus, commonly known as termites. [5][6]. A preliminary study found that vetiver essential oil may be a potential herbicide. This laboratory study examined the herbicidal activity of C. zizanoides and six different types of invasive weeds. Nootkatone was effective in inhibiting germination of these weeds. [2] The oil is used medicinally as a carminative, diaphoretic, diuretic, emmenagogue, refrigerant, stomachic, tonic, antispasmodic and sudorific. A stimulant drink is made from fresh rhizomes in India. The plants are used as an anthelmintic in Madya Pradesh (India). [2]

Traditionally, C. zizanioides is planted in southern India in strips as permanent field boundaries and occasionally in contour strips to control erosion, while in Java it is planted to protect sloping drains. Its use as an erosion-control plant spread throughout the tropics, but for a long time remained restricted to small areas. Recent interest started in Fiji, where it was grown in contour strips in sugar-cane plantations on steep slopes. Since the late 1980s, its planting for erosion control has been promoted strongly, not only around fields, but also to protect terraces and road shoulders. Strips of densely packed, stiff and tough grass stems break the speed of run-off water and divide it evenly, reducing the risk of formation of run-off streams and gully erosion. The very dense root system has a strong tendency to grow downwards and effectively anchors strips of plants and soil behind it. [2]

Preclinical Data

No documentation

Clinical Data

No documentation

Interaction & Depletion

No documentation

Dosage

No documentation

Poisonous Management

No documentation

Line drawing

113

Figure 1: The line drawing of C. zizanioides [2]

References

  1. The Plant List. Ver1.1 Chrysopogon zizanioides (L.) Roberty. [homepage on the Internet]. c2013 [updated 2013 Mar 23; cited 2016 June 17]. Available from: http://www.theplantlist.org/tpl1.1/record/kew-405169
  2. de Guzman CC, Oyen LPA. Vetiveria zizanioides (L.) Nash. In: Oyen LPA, Nguyen XD, editors. Plant Resources of South-East Asia No. 19: Essential-oil plants. Leiden, Netherlands: Backhuys Publisher, 1999;p. 167-172.
  3. Kim HJ, Chen F, Wang X, Chung HY, Jin Z. Evaluation of antioxidant activity of vetiver (Vetiveria zizanioides L.) oil and identification of its antioxidant constituents. J Agric Food Chem. 2005;53(20):7691-7695.
  4. Zhu BC, Henderson G, Chen F, Maistrello L, Laine RA. Nootkatone is a repellent for Formosan subterranean termite (Coptotermes formosanus). J Chem Ecol. 2001;27(3):523-531.
  5. Maistrello L, Henderson G, Laine RA. Comparative effects of vetiver oil, nootkatone and disodium octaborate tetrahydrate on Coptotermes formosanus and its symbiotic fauna. Pest Manag Sci. 2003;59(1):58-68.
  6. Lixin M, Gregg H, Roger AL. Germination of various weed species in response to vetiver oil and nootkatone. Weed Technol. 2004;18(2):263-267.