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Eleusine coracana (L.) Gaertn.
Poaceae
Ragi, Kurakkan, African millet, Finger millet
Source: James A. Duke. 1983. Handbook of Energy Crops. unpublished.
- Uses
- Folk Medicine
- Chemistry
- Description
- Germplasm
- Distribution
- Ecology
- Cultivation
- Harvesting
- Yields and Economics
- Energy
- Biotic Factors
- References
Ragi is the main food grain for many peoples, especially in dry areas of India
and Sri Lanka. Grain is higher in protein, fat and minerals than rice, corn,
or sorghum (Reed, 1976). It is usually converted into flour and made into
cakes, Puddings, or porridge. When consumed as food it provides a sustaining
diet, especially for people doing hard work. Straw makes valuable fodder for
both working and milking animals. A fermented drink or beer is made from the
grain. Grain may also be malted and a flour of the malted grain used as a
nourishing food for infants and invalids. Ragi is considered an especially
wholesome food for diabetics.
The leaf juice has been given to women in childbirth, and the plant is reported
to be diaphoretic, diuretic, and vermifuge (Watt and Breyer-Brandwijk, 1962).
Ragi is a folk remedy for leprosy, liver disease (Watt and Breyer-Brandwijk,
1962), measles, pleurisy, pneumonia, and small pox (Duke and Wain, 1981).
Per 100 g, the straw is reported to contain (ZMB): 3.7 g protein, 0.9 g fat,
87.3 g total carbohydrate, 35.9 g fiber, 8.1 g ash, 1110 mg Ca, 160 mg P, 260
mg Na, and 1500 mg K (C.S.I.R., 1948-1976). Per 100 g, the wet matter is
reported to contain (ZMB): 7.6 g protein, 1.1 g fat, 76.2 g total
carbohydrate, 33.6 g fiber, 15.1 g ash (Gohl, 1981). The plant yields
hydrocyanic acid (Watt and Breyer-Brandwijk, 1962).
Annual grass; culms erect, laterally flattened, 60-120 cm tall or long,
profusely tillering, in addition to branches sent out at the rounded nodes in
succession, plants often lodged or prostrate; root system fibrous and
remarkably strong, permeating soil thoroughly, inflorescence a whorl of 2-8
(normally 4-6), digitate, straight, or slightly curved spikes 12.5-15 cm long,
about 1.3 cm broad; spikelets about 70, arranged alternately on rachis, each
containing 4-7 seeds, varying from 1-2 mm in diameter; caryopsis nearly globose
to somewhat flattened, smooth or tugose, reddish-brown to nearly white or black.
Reported from the Hindustani and African Centers of Diversity, ragi or cvs
thereof is reported to tolerate alkali, disease, drought, fungus, high pH,
insects, laterite, low pH, mildew, salt, slope, and virus (Duke, 1978). Over
20 varieties of ragi are cultivated in India. The numerous races under
cultivation are primarily divided into purple and green types; those with
straight or open spikes, encurved or closed spikes, or branched spikes; length
of earheads (5-10 cm long); color of seeds (deep brown to shade of orange-red
to almost white or black); dwarf in habit (45 cm tall) to up to 1.3 m tall;
poor tillering to profuse tillering; early or late maturing; suitable for
growing under irrigation to growing in dry areas. Many named cultivars are
involved in breeding trials in India. Most improvement is sought in increasing
yields, resistance to lodging, even maturity and loose panicle. Strains of
white ragi, 'EC 1540', gives superior nutritive value, up to 14% protein,
compared to pigmented types, which range from 6-11%. 'Relluchodi' a hill type,
is green throughout, with long open type panicle and maturing in 115-120 days.
'AKP-2', is green throughout, with incurved panicle, maturing in 85-90 days.
E. coracana is mostly self-pollinated. (2n = 36)
Considered to be of Indian or African origin, perhaps a cultigen of the wild
species Eleusine indica. Widely cultivated in tropical Asia and East
Africa; cultivated on rainy slopes and upland areas of Himalayas up to 2,300 m
elevation.
Ranging from Cool Temperate Moist to Wet through Tropical Very Dry to Wet
Forest Life Zones, ragi is reported to tolerate annual precipitation of 2.9 to
42.9 dm (mean of 19 cases = 12.3) annual temperature of 11.1 to 27.4°C (mean
of 19 cases = 20.8) and pH of 5.0 to 8.2 (mean of 17 cases = 6.4) (Duke, 1978,
1979). Typically a tropical crop, one of the best suited for dry farming,
generally grown rainfed. Thrives under a medium rainfall, on porous soils that
do not get waterlogged. With rainfall of 53-75 cm, it is cultivated rainfed;
with less, it is irrigated. Ragi is very adaptable and thrives at higher
elevations than most other tropical cereals. Cultivated on soils ranging from
rich loams to poor shallow upland soils. In India, grown on black cotton
soils, but thrives on red lateritic loams. Ragi stands salinity better than
most cereals.
Ragi may be grown as a hot weather crop, from May to September, using long
duration varieties and as a cold season crop, from November and December, using
early types. Ragi seed are broadcast or drilled, in rows 7.5-30 cm apart. In
some areas, furrows are opened 25-30 cm apart and seeds sown along with
well-rotted manure. Seed rate varies from 21-38 kg/ha. Sometimes seed is sown
in nurseries and seedlings outplanted when 3-4 weeks old. Eleven kg seed
provides seedlings for a hectare. Transplanting is common where early rains
are uncertain. In India, two crops are sown: the early crop is grown from May
to August, and the main crop, from July to Novermber or early December. It is
also grown year-round under irrigation wherever water is available. Ragi is
monocropped in India under irrigation or transplantation. Rainfed it is mostly
intercropped with cereals, castor bean, niger, groundnut, pulses and gingeli.
The most common subsidiary crops grown with ragi are fieldbean (Lablab
purpureus), pigeon pea (Cajanus cajan), cowpea (Vigna
sinensis), and niger (Guizotia abysinnica). With groundnuts, ragi
is the subsidiary crop. Liberal manure, mainly sheep and cattle, is applied.
Green manures such as cowpeas, sunnhemp, artificial manures and oil cakes, have
been used on both irrigated and unirrigated crops. Artificial fertilizers are
usually applied near close of intercultural operations. Inorganic nitrogen
depresses crop yields on poor land, but enhances yields on fertile land.
Phosphate acts as a limiting factor controlling response to nitrogen. Minute
amounts of zinc sulfate increase yields of both grain and straw. Seed
inocculated with B. azotobacter increases yield. Ragi is chopped and
weeded at intervals of 14 days or so. The number and frequency of irrigations
varies with seasonal conditions. Ragi requires more water than jowar
(Sorghum bicolor) (Reed, 1976). Cowsik and Jayachandra (1981) found
that hardening ragi seeds with distilled water and phenolic acids (caffeic
acid, ferulic acid, and vanillic acid) hastened germination and imparted
resistance to the respective allelopathic agents; in addition, dry matter
production was increased by 10-40%.
Ragi matures 3-5 months after sowing, depending on variety, season and soil
properties. Rainfed crops are cut close to ground, stalks are allowed to
wither for a day or two in field, and then bundled and stacked for about 2
months before threshing. To separate the grains, dried earheads are beaten
with sticks, sheaves are trodden by bullocks or crushed by stone rollers.
Separated grains are winnowed and cleaned. Under irrigated conditions, crop is
harvested about 3.5 months after transplanting. Earheads are gathered when
they ripen; three or four pickings are usually required to collect all earheads
from a field. These are heaped up, and when dry, threshed. Straw from
irrigated plants is coarse and thick and is rarely cut. It is grazed down or
sometimes turned under as manure for next crop.
Seed yield is 5 MT/ha (Duke, 1978). Ragi grain possesses excellent storage
properties and is said to improve in quality with storage. Seed can be stored
without damage for as long as 50 years. They are highly valued as a reserve
food in times of famine. Yield depends on variety and is directly related to
duration, height and tillering capacity of type grown. Types with straight
spikes give better yields than those with curved spikes. Ragi is the principal
cereal crop for many peoples in India, Sri Lanka, and East Africa. In India
over 2.5 million hectares are cultivated annually. Although it does not enter
international markets, it is a very important cereal grain in areas of
adaptation.
According to the phytomass files (Duke, 1981b), annual productivity ranges from
2 to 9 MT/ha. Yields under irrigated conditions are nearly double those on
rainfed land. Yield of straw varies from 1.1-2.2 MT/ha from rainfed crops, and
4.4-8.8 MT/ha from irrigated crops. Grain yield is correlated with plant
height, grain weight of main ear and days to 50% maturity. In Punjab, where
ragi is grown mainly for fodder, yields of green fodder average 13.5 MT/ha in
three cuttings (Reed, 1976). Bogdan (1977) reports 15 MT green fodder/ha in 3
cuts; and for straw, 1.12-2.24 MT/ha for dryland crops and up to 8.96 MT for
irrigated crops.
Ragi is subject to relatively few serious diseases or pests. Fungi reported on
ragi include: Cladosporium herbarum, Cercospora fusimaculans, Cochliobolus
nodulosus, Curvularia lunata, Helminthosporium leucostylum, H. nodulosum
(leafspot or blight), H. tetramera, Melanopsichum eleusinis (smut),
Pellicularia rolfsii, Phyllachora eleusine, Piricularia eleusine, P. grisea, P.
oryzae, P. setariae, Sclerospora macrospora, Sclerotium rolfsii. A strain
of sugarcane mosaicz virus also attacks ragi. Ragi is parasitized by the
following species of Striga: S. asiatica, S. densiflora, S. hermonthica,
and S. lutea. Nematodes known to attack ragi include:
Meloidogyne sp., and Scutellonema sp. Insect pests
include: hairy caterpillar (Amsacta albistriga), Jola grasshopper
(Colemania sphenarioides), ragi pink shoot-borer (Sesamia
inferens), and ragi leaf-roller (Marasamia trapezalis). In storage,
a beetle (Alphitobius sp.) may cause some damage.
- Bogdan, A.V. 1977. Tropical pasture and fodder plants. Longman, London.
- Cowsik, R.S. and Jayachandra. 1981. Hardening with phenolic acids to resist
inhibitors and enhance dry matter production. Comp. Physiol. Ecol.
6(2):111-115.
- C.S.I.R. (Council of Scientific and Industrial Research). 1948-1976. The wealth
of India. 11 vols. New Delhi.
- Duke, J.A. 1978. The quest for tolerant germplasm. p. 1-61. In: ASA Special
Symposium 32, Crop tolerance to suboptimal land conditions. Am. Soc. Agron.
Madison, WI.
- Duke, J.A. 1979. Ecosystematic data on economic plants. Quart. J. Crude Drug
Res. 17(3-4):91-110.
- Duke, J.A. 1981b. The gene revolution. Paper 1. p. 89-150. In: Office of
Technology Assessment, Background papers for innovative biological technologies
for lesser developed countries. USGPO. Washington.
- Duke, J.A. and Wain, K.K. 1981. Medicinal plants of the world. Computer index
with more than 85,000 entries. 3 vols.
- Gohl, B. 1981. Tropical feeds. Feed information summaries and nutritive values.
FAO Animal Production and Health Series 12. FAO, Rome.
- Reed, C.F. 1976. Information summaries on 1000 economic plants. Typescripts
submitted to the USDA.
- Watt, J.M. and Breyer-Brandwijk, M.G. 1962. The medicinal and poisonous plants
of southern and eastern Africa. 2nd ed. E.&S. Livingstone, Ltd., Edinburgh
and London.
Complete list of references for Duke, Handbook of Energy Crops
last update July 10, 1996