Echinochloa (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Echinochloa P. Beauvois

Protologue: Ess. agrost.: 53 (1812).

Family: Gramineae

Chromosome number: x= 9; 2n= 6x= 54 (E. colona cv. group Frumentacea,E. crus-galli cv. group Esculenta).

Major taxa and synonyms

• Echinochloa colona (L.) Link cv. group Frumentacea, Hort. Berol. 2: 209 (1833); cv. group name proposed here. Synonyms: E. frumentacea (Roxb.) Link (1827), E. crus-galli (L.) P. Beauvois var. frumentaceum (Link) Trimen (1885), E. colona (L.) Link var. frumentaceum (Roxb.) Ridley (1925).

• Echinochloa crus-galli (L.) P. Beauvois cv. group Esculenta, Ess. agrost.: 53, 161 (1812); cv. group name proposed here. Synonyms: Panicum esculentum A. Braun (1861), E. utilis Ohwi & Yabuno (1962), E. esculenta (A. Braun) H. Scholz (1992).

Vernacular names

General:

• Barnyard millet (En)
• Vietnam: lồng vực.

E. colona cv. group Frumentacea:

• Indian barnyard millet, sawa millet, shama millet (En). For wild E. colona : jungle rice (En)
• Indonesia: tuton, watuton (Javanese), jajagoan leutik (Sundanese)
• Malaysia: padi burong, rumput kusa-kusa
• Philippines: pulang-puwit (Tagalog), guinga (Visaya), dakayang (Ilokano)
• Burma (Myanmar): myet-thi, pazun-sa-myet
• Laos: khauz nôk
• Thailand: ya-noksichomphu (central), ya-nokkhao (northeastern)
• Vietnam: cỏlồng vực, cỏnúc, cỏlồng vực hạt.

E. crus-galli cv. group Esculenta:

• Japanese barnyard millet, Japanese millet (En). For wild E. crus-galli : barnyard grass, cock's foot (En). Crête-de-coq, pattes de poule (Fr)
• Indonesia: jawan (Javanese), jajagoan (Sundanese), gagajahan (Sundanese)
• Malaysia: padi burong, rumput kekusa besar
• Philippines: bayokibok (Tagalog), lagtom (Bikol), marapagay (Ilokano)
• Burma (Myanmar): myet-ihi
• Cambodia: smao bek kbol
• Thailand: ya-plonglaman, ya-khaonok (central)
• Vietnam: cỏlồng vực.

Origin and geographic distribution

Indian barnyard millet most probably originated from India where it has been domesticated from the wild E. colona. Wild E. colona originated from the tropics and subtropics of the Old World but can now be found in the tropics and subtropics all over the world and is very common in South-East Asia. Indian barnyard millet is known from ancient Egypt and East Africa but is at present widely grown as a cereal only in India, Kashmir and Sikkim. It has been introduced into the United States, Canada and Australia, especially as a forage. In continental South-East Asia, Indian barnyard millet is quite commonly cultivated but in Peninsular Malaysia it only occurs as a rare weed in cultivated fields.

Japanese barnyard millet most probably originated from Japan where it was domesticated from the wild E. crus-galli some 4000 years ago, and was later introduced into Korea, China and adjacent Russia as a cultivated cereal. Wild E. crus-galli is native to temperate Europe and Asia but has spread to temperate and tropical areas all over the world; it is also very common in South-East Asia. Japanese barnyard millet is only extensively cultivated in Japan, Korea and northern China.

In non-continental South-East Asia both barnyard millets are rare at present. However, it is thought that formerly one or both barnyard millets were commonly cultivated in Java. It is even believed that the name "Java", meaning "millet island", refers to the abundant occurrence of one or both barnyard millets in former times.

Uses

In areas where the culta are grown as cereals, they are also used, prepared and eaten as cereals. The grains are cooked in water like rice, or parched and boiled with milk and sugar. They are also sometimes mixed with rice and fermented to make beer. In South-East Asia, both taxa and culta are used as grain crops in times of food scarcity. The coarse, tough seed coat and the characteristic flavour make barnyard millet less popular among rice and wheat eaters. The seed is used as a feed for cage birds. Although the wild taxa can be troublesome weeds, especially in paddy rice, they are used as excellent forages which can also be fed as hay. In Java, young shoots of both barnyard millets are eaten as a vegetable.

Production and international trade

Both barnyard millets are not of great importance and are only locally produced, used and traded. Often they are grown as a substitute for rice when the paddy crop has failed. No statistics are available. World production of all millets together amounted to 36 million t in 1993 (pearl millet (Pennisetum glaucum (L.) R. Br.) 40%, foxtail millet ( 'Setaria italica (L.) P. Beauvois) 24%, proso millet (Panicum miliaceum L.) 15%, finger millet (Eleusine coracana (L.) Gaertner) 11%, other millets (including barnyard millet) 10%). Millet production has been declining annually by about 2% since the 1980s. In Japan, barnyard millet cultivation fell from 104 000 ha in 1880 to 5000 ha in 1970.

Properties

The approximate composition of the grain of Indian barnyard millet per 100 g edible portion is: water 11.9 g, protein 6.2 g, fat 2.2 g, carbohydrates 65.5 g, fibre 9.8 g and ash 4.4 g. Barnyard millet protein lacks gluten and therefore the millet alone is unsuitable to prepare bakery products. Compared with wheat and rice starches, the starch of barnyard millet has a higher gelatinization temperature, a higher water-binding capacity and a slower enzymatic hydrolysis. Because the release of sugars from millet-based diets is slow, millets are considered a good food for diabetics. The protein content of Japanese barnyard millet is nearly twice as high as that of polished rice. A mixture of 7 parts polished rice and 3 parts barnyard millet provides a favourable nutritive balance. The straw is considered superior to that of rice, oats or timothy in protein and calcium content.

The 1000-grain weight of barnyard millet is 3-4 g.

Description

• Annual or perennial herbs.
• Leaves usually without a ligule.
• Inflorescence consists of racemes arranged along a central axis; spikelets paired or in short secondary small racemes, typically densely packed in 4 rows, narrowly elliptical to subrotund, flat on one side, gibbous on the other, often hispidulous, sometimes prolonged at the base into a short cylindrical stipe, cuspidate or awned at apex.
• Florets 2, the lower staminate or neuter, the upper perfect; glumes acute to acuminate, about one third the length of the spikelet; lower lemma often stiffly awned; upper lemma terminating in a short membranous, laterally compressed, incurved beak; upper palea acute, the tip briefly reflexed and slightly protuberant from the lemma.

E. colona cv. group Frumentacea:

• Erect or geniculate ascending, often tufted annual, 0.6-2.4 m tall.
• Culm slender to robust; slender plants decumbent with strongly branched culms, rooting from the lower nodes; robust plants erect, only branching at the upper nodes.
• Leaf sheath glabrous, usually longer than the internode; ligular area minutely pubescent; leaf blade linear, 8-38 cm × 0.6-4 cm, subglabrous.
• Inflorescence usually erect, in decumbent plants with short racemes appressed to the triquetrous rachis, in erect plants with spreading lower racemes giving the inflorescence a larger pyramidal shape; pedicel 2-4-nate, up to 2 mm long; spikelet persistent, 2-4 mm long, acute but never awned; glumes and lower lemma typically membranaceous; lower glume about one third the length of the spikelet, upper glume somewhat shorter than the spikelet, ciliolate; lower lemma similar to upper glume; lower floret sterile, upper floret bisexual.
• Caryopsis broadly ellipsoid, 2-3 mm long, 1-2 mm wide.

E. crus-galli cv. group Esculenta:

• Erect, tufted annual, up to 1 m tall.
• Culm usually robust, simple or branched from the upper nodes. Leaf sheath glabrous, usually longer than the internode; ligular area glabrous; leaf blade linear, 15-40 cm × 0.5-2.5 cm, glabrous.
• Inflorescence erect or slightly nodding, with spike-like racemes that are erect or sometimes incurved at the tip; primary axis densely white setose at the nodes; racemes 10-25, 1-5 cm long, purple, subsessile, densely multispiculate; rachis compressed and angular; pedicel short and mostly 2-nate; spikelet persistent, 3-4 mm long, shortly cuspidate, rarely awned; glumes and lower lemma chartaceous; lower glume about one third the length of the spikelet; upper glume usually shorter than the spikelet, cuspidate, veins and margins sometimes subspinulose; lower lemma similar to upper glume; lower floret sterile, upper floret bisexual.
• Caryopsis 2-3 mm long and wide.

Growth and development

Barnyard millet is a very fast-growing grass. Seed germinates quickly, axillary shoots develop already in the second week after emergence and flowering starts 2-3 weeks later. It is self-pollinated. The wild forms flower throughout the year and form seed abundantly, provided sufficient water is available. E. crus-galli flowers earlier and more abundantly under short-day circumstances, but under long-day conditions all parts are robuster. Its seeds, especially of the weedy types, may show a rather long dormancy period of several months. In India, some cultivars of Indian barnyard millet mature in about 6 weeks. The crop cycle of Japanese barnyard millet varies from 65-115 days.

Other botanical information

Echinochloa is a difficult genus, forming a complex of probably 30-40 species which are not reliably distinguishable from each other because of numerous intermediate forms. Its great diversity is caused by self pollination combined with easy adaptation to a wide range of aquatic and ruderal habitats. The genus can usually be recognized by its bristly sharp-pointed or awned spikelets in 4 rows with a recurved palea tip as best diagnostic character. Much confusion about names and identities exists and a thorough taxonomic revision is urgently needed.

The taxa and culta of E. colona and E. crus-galli are not easy to distinguish from each other. In general, E. colona is a more tropical grass with awnless, smaller spikelets having membranous glumes and E. crus-galli is a more temperate grass with awned, larger spikelets having chartaceous glumes, although awnless E. crus-galli occurs as well. In general, the culta are robuster plants, with larger and denser inflorescences bearing persistent spikelets. Hybrids between E. colona and E. crus-galli are sterile (both the wild and cultivated forms), but within each individual species, hybrids between the wild and cultivated forms are fully or at least partly fertile.

In India, 4 cultivar subgroups (races) can be distinguished within Indian barnyard millet (Intermedia, Laxa, Robusta, and Stolonifera), differing in qualitative and quantitative characteristics; some differences are (average values given in the sequence in which the 4 cv. subgroups were mentioned above): days to 50% flowering: 46, 63, 60, 46; plant height: 81, 111, 128, 70 cm; number of basal tillers: 11, 7, 6, 21; panicle length × width: 13 cm × 3 cm, 22 cm × 3 cm, 21 cm × 4 cm, 11 cm × 2 cm; number of primary inflorescence branches (racemes): 23, 39, 47, 16; raceme length: 28, 69, 31, 22 mm; number of spikelet rows: 5, 4, 5, 4. Farmers commonly grow several different subgroups together in the same field. The Indian cultivars include "Anurag" (matures in 80 days), "Gujarat" and "Banti" (maturing in 80-90 days) and "VI Madira" (matures in 90-100 days).

E. oryzoides (Ard.) Fritsch (synonym: E. crus-galli var. oryzicola (Vasinger) Ohwi) is native to Asia but has also been introduced into rice-growing regions of Australia, the United States (California) and Europe. It is a serious weed in rice fields, difficult to eradicate because it mimics the rice crop. It comes into flower a few days earlier than the rice crop and it disperses seed before the rice is harvested. In the Russian Caucasus, a cultivar of E. oryzoides (known as E. macrocarpa Vasinger) lacks the ability to disperse seed efficiently. It is harvested as a crop and used for alcohol distillation or cake baking.

E. stagnina (Retzius) P. Beauvois is another serious weed of paddy rice in tropical Asia and Africa. It has an aquatic habit with creeping stems and can be distinguished from E. colona and E. crus-galli by the presence of a ligule. It is renowned as a good forage plant and as a cereal in times of food scarcity. In Niger (Africa), a sweet drink is prepared from sap of the stem; a kind of sugar can also be extracted from this sap.

Ecology

Barnyard millet has a C₄-cycle photosynthetic pathway. In general, Indian barnyard millet is more tropical and Japanese barnyard millet more temperate, but both may occur up to 1000 m altitude in the tropics. Japanese barnyard millet is more tolerant of low temperatures than Indian barnyard millet. The optimum climatic requirements of the barnyard millets are similar to those of paddy rice, although in practice they are mostly grown in dry and less fertile locations where rice will not grow well.

Propagation and planting

Propagation is usually by seed, but is also possible by planting rooted tillers. If stored dry, seed can remain viable for several years. At the beginning of the rainy season, seed is broadcast or drilled in rows 20-25 cm apart and 10-15 cm within the rows, at a seed rate of 7-10 kg/ha. A density of at least 15 000 plants/ha is required. It is usually grown as a rainfed crop, but can be grown under irrigation and in waterlogged areas as well.

Husbandry

The crop responds well to weeding and ample fertilization (farmyard manure, 40 kg/ha N and 9 kg/ha P), but normally it receives little attention and is not manured. In southern India, where Indian barnyard millet is grown as a cereal, it is often intercropped with finger millet or foxtail millet. A rotation of Indian barnyard millet with pea, wheat or chickpea was found to be advantageous both for total yields and total returns in India.

Diseases and pests

The crop may suffer from shoot smut caused by Ustilago crus-galli and from head smut caused by Ustilago panici-frumentacei. Shoot smut causes gall-like swellings on the stem and deformed inflorescences; the disease is seedborne and can be controlled with organomercurial fungicides. Head smut causes swelling of the ovaries; it is seedborne and can be controlled by several fungicides (e.g. ceresan, bovistin). Shoot fly (Atherigona spp.) is a major pest of small millets.

Harvesting

Indian barnyard millet can be harvested from about 6 weeks after sowing onwards depending on cultivar.

Japanese barnyard millet is harvested 30-40 days after flowering when the racemes have turned brown. Plants are cut off at their base with a hand sickle, bundled and dried in the field for 20 days. The infructescences are soaked or heated with steam, dried and subsequently threshed.

Yield

Yields of Indian barnyard millet amount to 700-800 kg/ha of grain and 1000-1500 kg/ha of straw. It is believed that it can reach a grain yield of more than 2 t/ha. As a forage crop in the United States it can produce as many as eight crops per year.

Average yield of Japanese barnyard millet is 1.65 t/ha.

Handling after harvest

The milling process may include husking, debranning and grinding. The husked grains are polished. Polished grain may be ground to flour. The grain can also be cooked like rice or processed for flaking.

Genetic resources and breeding

Germplasm collections of barnyard millet are present in India (Bangalore, 800 accessions) and in Japan (National Northeast Agricultural Experiment Station Tohoku, 120 accessions). Breeding programmes (mainly for higher yield and disease resistance) are in progress in India.

Prospects

In the regions where barnyard millet is at present most widely grown, it is mainly restricted to marginal lands where rice and other crops will not grow well. In South-East Asia, it will remain an emergency crop, giving at least some produce in a short time when rice has failed. In the near future, the position of barnyard millet is unlikely to improve.

Literature

• Baudet, J.C., 1981. Les céréales mineures [The minor cereals]. Echinochloa. Agence de Coopération Culturelle et Technique, Paris, France. pp. 48-55.
• de Wet, J.M.J., Prasada Rao, K.E., Mengesha, M.H. & Brink, D.E., 1983. Domestication of sawa millet (Echinochloa colona). Economic Botany 37: 283-291.
• Lazarides, M., 1994. Echinochloa. In: Dassanayake, M.D. (Editor): A revised handbook to the flora of Ceylon. Vol. 8. Amerind Publishing Company, New Delhi, India. pp. 180-189.
• Malleshi, N.G., 1990. Processing of small millets for food and industrial uses. In: Seetharam, A., Riley, K.W. & Harinarayana, G. (Editors): Small millets in global agriculture. Aspect Publishing, London, United Kingdom. pp. 326-339.
• Manidool, C., 1992. Echinochloa colona (L.) Link, Echinochloa crus-galli (L.) P. Beauv. In: 't Mannetje, L. & Jones, R.M. (Editors): Plant Resources of South-East Asia No 4. Forages. Pudoc Scientific Publishers, Wageningen, the Netherlands. pp. 125-127.
• Purseglove, J.W., 1972. Tropical crops. Monocotyledons 1. Longman, London, United Kingdom. pp. 144-146.
• Yabuno, T., 1966. Biosystematic study of the genus Echinochloa. Japanese Journal of Botany 19: 277-323.
• Yabuno, T., 1987. Japanese barnyard millet (Echinochloa utilis, Poaceae) in Japan. Economic Botany 41: 484-493.

Authors

• S. Partohardjono & P.C.M. Jansen