Juncus effusus (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Juncus effusus L.

Protologue: Sp. pl.: 326 (1753).

Family: Juncaceae

Chromosome number: 2n= 40

Juncus communis E. Mey. (1819), J. sundaicus Ridl. (1935).

• Soft rush, common rush, mat rush (En). Jonc à lier, jonc épars (Fr)
• Indonesia: sumpu, udulan (Javanese)
• Philippines: sudsud (Igorot), pingot, balili (Bontoc)
• Vietnam: cây bấc, bấc dèn, dăng tâm thảo.

J. effusus is widely distributed in the temperate zones of the world, especially in the northern hemisphere, and the mountainous parts of the tropics, but it is not found in Australia. It is native to South-East Asia where it is found in Malaysia (Sabah, Sarawak), Indonesia (Aceh, Java, Kalimantan), the Philippines (from Luzon to Mindanao), New Guinea, northern Thailand and Vietnam. J. effusus is cultivated in Japan, China, Taiwan, the Philippines and northern Vietnam. It is sometimes considered a weed, for instance in pastures.

The stems of J. effusus are widely used for making mats, for instance in Japan ("tatami" floor mats), Taiwan, China, Korea, the Philippines and Vietnam. They served for basket weaving in Roman times and are still used for this purpose. They are also made into bags, hats, chair seats and other products, for example in the Philippines. The stems are used for tying parcels in China and have been imported into Peninsular Malaysia for this purpose. The pith was formerly made into lamp-wicks in Europe and Japan and may still be used for this purpose in China and Vietnam. J. effusus can be pulped for paper making.

In Peninsular Malaysia the pith is imported from China and used as a drug ("sumbu china"), e.g. against urinary problems. In China and Vietnam it is credited with antilithic, pectoral, discutient, refrigerant, diuretic, depurative and sedative properties and it is used to keep fistulous sores open. The root is also considered to be diuretic. J. effusus is readily eaten by goats but rarely by sheep, and is reported to be poisonous to cattle. It may have potential for wastewater treatment, but in comparative studies it showed less biomass production and nutrient accumulation than species such as Phragmites australis (Cav.) Trin. ex Steudel and Schoenoplectus lacustris (L.) Palla.

In 1989 and 1990 the production of J. effusus stems in Japan was 90 000-100 000 t per year from an area of about 8 400 ha. Statistics on production in other countries and international trade are not available.

The stems of J. effusus consist of outer layers of sclerenchyma, providing durability to the weaving material, and an inner core of spongy tissue, providing elasticity. Commercial dried stems (7% moisture) contain 33% fibre. Air-dried stems contain about 35-40% cellulose and 3.5-4.5% lignin.

A range of free and glucosylated dihydrophenantrenes have been isolated from the aerial parts of J. effusus , with the free dihydrophenantrenes showing strong antialgal activity against Raphidocelis subcapitata (synonym: Selenastrum capricornutum ) and cytotoxic activity in the brine shrimp assay. Dihydrophenanthrenes from J. effusus showed varying levels of toxicity to other freshwater organisms. Other compounds isolated from the aerial parts include cycloartane glucosides and cycloartane triterpenes. Phenanthrene derivatives and phenolic compounds such as p-coumaric acid and vanillic acid have been isolated from the pith. An ethylacetate pith extract has shown antioxidant and antiviral activity. The dry matter digestibility is about 33% and the N concentration of dried plants is 1.2-1.4%.

The 1000-seed weight is about 10 mg.

Various Cyperaceae and Pandanaceae may be used for weaving instead of J. effusus .

A semi-aquatic, sedge-like, densely tufted, erect, glabrous, rhizomatous, perennial herb, 40-120 cm tall. Rhizome tough, creeping-horizontal, short, very short-jointed, scaly. Stem terete with continuous pith, 1-3 mm thick, not or hardly ribbed (when dried very closely-set faint longitudinal ribs are visible). Leaves represented by basal scale-like sheaths; sheaths several, stem-embracing, red-brown, bladeless, obtuse, 5-12 cm long, often with a deciduous awn at apex. Inflorescence a pseudolateral, dense or lax, usually many-flowered cymose panicle 1-10(-15) cm long; bract of the inflorescence erect, terete, acute at apex, simulating a continuation of the stem, overtopping the inflorescence by 14-25 cm; flowers partly sessile, partly stalked with petiole up to 8 mm long; floral bracts 2, very close together, ovate, about 0.7-0.8 mm long, thin; perianth segments 6, subequal, narrowly ovate-lanceolate, 2-3.5 mm long, firm with transparent thin margins, apex very acute, yellowish to pale green; stamens 3(-6), much shorter than the tepals, anthers scarcely 1 mm long, equalling or shorter than the filaments; pistil with sessile ovary, very short style, stigmas 3, filiform, long, erect. Fruit a 3-valved capsule, trigonous-oblong, 2-3 mm long, brown, with numerous seeds. Seed broadly ellipsoid, about 0.4-0.5 mm long, apiculate, finely reticulate.

The time to flowering of J. effusus cultivars in Japan is influenced by the photoperiod, with longer photoperiods resulting in earlier flowering. The extent of the photoperiod response differs among cultivars. Cultivar choice and cultural methods in Japan are aimed at preventing flowering, because the stem becomes more fragile when flowering starts. In Japan J. effusus is sown in early December and harvested 7-8 months later, in July. In Java J. effusus flowers year-round. J. effusus seedlings have shown autotoxic sensitivity to extracts of dead aboveground tissues of adult plants.

Juncus L. contains about 225 species, widespread over both hemispheres but particularly in temperate and cold regions. J. effusus is extremely variable and many varieties and forms have been distinguished. J. effusus L. var. decipiens Buchenau (synonym: J. decipiens (Buchenau) Nakai) is a form with fruits that are less obtuse at the apex. This variety is cultivated in Japan and its many cultivars have been classified into 3 types:

• elongate type, with long, thick and firm stems, less tillering but flowering abundantly; mats made of it are durable but inferior in colour, lustre, uniformity and elasticity;

• tiller type, with short, thin and soft stems, more tillering and flowering poorly; mats made of it have a good colour, lustre, elasticity and dye-absorbing capacity;

• intermediate type, with intermediate characteristics between the elongated and tiller types.

There is no information as to whether other Juncus species found in South-East Asia, such as J. inflexus L. and J. prismatocarpus R. Br. are used as fibre plants. J. inflexus has distinctly ribbed stems and its flowers have 6 stamens; it occurs in Europe, Africa and Asia. J. prismatocarpus has slightly smaller stems up to 1 m tall and a terminal inflorescence with its bract not continuous with the stem; it occurs from India throughout South-East Asia to Australia and New Zealand.

J. effusus is found in wet locations, such as pools, swamps, lake borders and river banks. In South-East Asia, where it occurs at 1200-3000 m altitude, it is locally abundant, but generally rare. The base and optimum temperatures for tillering of J. effusus var. decipiens have been found to be about 3°C and 16°C, respectively, with adequate tillering occurring in a temperature range of 11-21°C. In cultivation J. effusus prefers fertile clay, clay-loam or loam soils with pH 6. The rhizomes are less tolerant of low oxygen conditions than those of Schoenoplectus lacustris (L.) Palla and Typha spp. In Europe natural stands of J. effusus are often indicative of disturbed, nutrient-rich soils which are low in lime.

J. effusus is mainly propagated through clump division after the stems have been harvested; it can also be propagated by rhizome parts and seed. In Japan a common method is to divide a parent plant into 10 parts, which are planted 15 cm × 15 cm apart in heavily fertilized nursery beds. After 4-5 months they are subdivided into 10 pieces again, each with 7-10 tillers. These pieces are planted out in flooded and puddled fields at a spacing of 15-18 cm × 15-18 cm, resulting in a plant density of 300 000-450 000 plants/ha. In Japan J. effusus is often grown in rotation with rice, the former in the winter and the latter in the summer.

In vitro plant regeneration of J. effusus is possible. Transplanting of 6-8 day old seedlings on Murashige and Skoog (MS) medium gives multiple shoot formation within 4 weeks. Addition of benzyladenine (BA) or 2isopentenyladenine (2iP) improves regeneration. Rooting is induced by transferring the shoots to MS medium with NAA (naphthalenacetic acid).

In Japan J. effusus is weeded 3-4 times and heavily fertilized with about 400 kg N, 40 kg P, 270 kg K. About 60 kg N and 35 kg P per ha are applied at planting, whereas most N, some P and all K are given in 5-6 top dressings. In addition 10 t manure is applied per ha. The crop is grown in a waterlogged culture with frequent draining to prevent rotting and to promote tillering. Sometimes the tops of the plants are clipped to a height of 40-45 cm to promote simultaneous tillering, and to decrease tip rot and lodging. Lodging is also prevented by covering the field with nets at a height of 80-100 cm. The field is drained 10 days before harvesting.

Information on diseases and pests affecting J. effusus in South-East Asia is not available. In Japan the most serious disease is stem rot or sheath blight caused by Rhizoctonia . Damage can be reduced by planting resistant cultivars. Minor diseases in Japan are blight caused by Leptosphaeria juncina and frog-eye spot caused by Cercospora juncicola .

Serious pests in Japan are the stem worm Bactra honesta and the mat rush sawfly Eutomostethus juncivorus .

In Japan J. effusus stems are usually harvested at dusk. Here, harvesting comprises cutting, selecting and bundling. At harvest time the number of tillers per clump has increased from the original 7-10 to about 100.

Average J. effusus yields in Japan have been stable at about 10 t/ha of weaving material (dried stems) for a long time. Yields of 14 t/ha are considered good.

In Japan the harvested stems of J. effusus are coated with soil to ensure they do not lose their natural colour. Coating is done by soaking the stems in muddy water, after which the coated bundles are placed upright to drain. The stems are then spread on the ground for 2-3 days and dried in the sun from 9 a.m. to 3 p.m. The stems may also be dried artificially, sometimes after initial drying in the sun for 1 day. In Japan the material is graded into 3 length classes for mat-weaving: A (over 110 cm long), B (97-110 cm) and C (70-97 cm). Stems 60-70 cm long are used for other articles, such as hats, cushions and bags, whereas shorter stems are discarded at harvest.

A fine straw for weaving can be prepared by splitting the stems, removing the pulp and drying the remaining part quickly in the sun to make it curl up. Flat straw can be made by removing the pulp, flattening the stems and drawing them between the thumb and a piece of wood. Sometimes the stems are heated in boiling water for 10 minutes to give the product more elasticity and resistance. For medicinal use in Vietnam stems are steamed and peeled, leaving the pith.

It is probable that germplasm collections of J. effusus are kept in Japan and perhaps in other countries where the crop is cultivated, but information is not available.

Breeding and selection work on J. effusus is carried out in Japan. Japanese lines that produce high straw yields of good quality have been introduced, tested and registered in China.

In view of the availability of other weaving and tying material, e.g. from various Pandanaceae and Cyperaceae , the role of J. effusus in South-East Asia will probably remain very limited, though it may have some potential as a local source of weaving material for domestic use in high-altitude regions, for instance in the Philippines.

 1 Backer, C.A., 1951. Juncaceae. In: van Steenis, C.G.G.J. (Editor): Flora Malesiana. Series 1. Vol. 4. Noordhoff-Kolff N.V., Jakarta, Indonesia. pp. 210-215. 2 della Greca, M., Fiorentino, A., Monaco, P., Pinto, G., Pollio, A. & Previtera, L., 1996. Action of antialgal compounds from Juncus effusus L. on Selenastrum capricornutum. Journal of Chemical Ecology 22(3): 587-603. 3 Hanai, Y., 1974. Mat rush growing in Japan. World Crops 26: 122-126. 4 Hanai, Y. & Kobayashi, H., 1972. Varietal differences in the photoperiodic responses of rush plants (Juncus decipiens Nakai). Proceedings of the Crop Science Society of Japan 41: 367-371. 5 Shima, K., Toyota, M. & Asakawa, Y., 1991. Phenanthrene derivatives from the medullae of Juncus effusus. Phytochemistry 30(9): 3149-3151. 6 Venema, K.C.W., 1959. Some notes regarding the cultivation and fertilization of matting-grass (Juncus effusus L., var. decipiens F.B.). Potash and Tropical Agriculture 2(2): 14-29.

Y. Umi Kalsom