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Chloris gayana Kunth

Poacea
Rhodesgrass

Source: James A. Duke. 1983. Handbook of Energy Crops. unpublished.


  1. Uses
  2. Folk Medicine
  3. Chemistry
  4. Description
  5. Germplasm
  6. Distribution
  7. Ecology
  8. Cultivation
  9. Harvesting
  10. Yields and Economics
  11. Energy
  12. Biotic Factors
  13. References

Uses

Rhodesgrass is one of the best grasses for rotation grasslands in tropical and subtropical areas, useful for establishment of pasture leys. It is suitable for silage and hay, as well as for fodder. Liked by all kinds of stock, it may cause skin troubles in horses. Its ability to establish rapidly makes it valuable for soil conservation (Reed, 1976). Persistent and drought resistant when well managed, but ephemeral if poorly managed (Gohl, 1981).

Folk Medicine

No data available.

Chemistry

As % of dry matter
DM CP CF Ash EE NFE
Fresh pasture, Zimbabwe 28.2 8.9 37.9 6.0 1.0 46.2
Fresh, first cutting, early bloom Tanzania 20.0 9.5 32.5 11.8 1.7 44.5
Fresh, second cutting, early bloom Tanzania 25.0 7.1 38.7 10.2 1.0 43.0
Fresh, mature, Hawaii 28.8 8.0 37.2 13.1 2.0 39.7
Hay, dry season, 6 weeks, 55 cm, Thailand 84.1 9.9 33.4 8.9 27.0 45.1
Hay, dry season, 8 weeks, 60 cm, Thailand 91.5 9.0 35.6 8.3 2.5 44.6
Hay, dry season, 10 weeks, 95 cm, Thailand 88.1 6.8 36.5 8.6 2.4 45.7
Hay, dry season, 12 weeks, 95 cm, Thailand 90.1 4.1 38.2 6.7 1.8 49.2
Hay, first cutting, Tanzania 87.0 3.7 43.5 8.7 1.3 42.8
Hay, second cutting, Tanzania 87.0 3.7 42.0 8.7 1.2 44.4
Silage, Nigeria 23.6 4.5 37.2 13.4 2.2 42.7
Digestibility (%)
Animal CP CF EE NFE ME
Pasture Cattle 62.3 75.2 36.0 67.4 2.42
First cutting Sheep 69.5 83.7 47.0 77.8 2.58
Second cutting Sheep 62.0 74.4 30.0 63.3 2.24
Mature Oxen 58.0 70.0 50.0 60.0 2.08
Hay, 6 weeks Sheep 55.0 60.0 45.0 56.0 2.81
Hay, 8 weeks Sheep 54.0 62.0 54.0 56.0 2.01
Hay, 10 weeks Sheep 43.0 61.0 58.0 55.0 1.95
Hay, 12 weeks Sheep 17.0 51.0 36.0 52.0 1.71
Hay, first cutting Sheep 31.4 56.6 46.0 50.9 1.77
Hay, second cutting Sheep 32.4 55.5 42.0 46.6 1.68
Silage Cattle 8.9 72.0 22.7 52.7 1.83
After Gohl, 1981

Description

Perennial or annual grass, variable in habit, 0.6–1.6 m tall, forming tufts, sometimes rhizomatous and spreading by rooting stolons; shoot-bases, and leaf-sheaths compressed; leaf-blades flat or folded, 12.5–45 cm long, 10–20 mm wide; inflorescence of 6–15 one-sided spikes, clustered at end of stem; spikes 5–10 cm long with numerous spikelets, green, turning to copper-brown at maturity; spikelets 3–4 mm long with 3–4 florets; glumes unequal, the lower 3 mm long and fertile, with an awn up to 5 mm long; the upper florets much smaller and usually sterile. Seeds 3.3–4.4 million per kilogram (Reed, 1976).

Germplasm

Reported from the African Center of Diversity, Rhodesgrass, or cvs thereof, is reported to tolerate alkali, drought, frost, high pH, low pH, nematodes, poor soil, salt, sand, slope, and weeds (Duke, 1978). The plant may be more sensitive to Lithium than beet, but it is relatively tolerant. Numerous ecotypes or natural strains with different agricultural value occur in Kenya. 'Nzoia' strain originated near the river of that name and is in commercial seed production; it is persistent under intensive grazing and of high pasture value. 'Giant Rhodes' (Mpwapwa Rhodes), is very frost-tender; 'Katambora Rhodes' is moderately frost-resistant. Stoloniferous forms usually compete with weeds better than tufted forms. Most seed on commercial markets is from cultivars of Australian origin.(Reed, 1976). (2n = 20, 30, 40)

Distribution

Native to South and East Africa, in areas from 660 to over 2160 m altitudes. It was introduced into India from South Africa, and later into North America (Gulf Coast and California under irrigation), Australia (especially in Queensland), South America (Brazil, Argentina, and Uruguay), North Africa, and Philippine Islands.

Ecology

Ranging from Cool Temperate Wet to Steppe through Tropical Desert to Wet Forest Life Zones, Rhodesgrass is reported to tolerate annual precipitation of 3.1 to 40.3 dm (mean of 30 cases = 12.6) annual tamperatures of 8.4 to 27.8°C (mean of 30 cases = 20.3), and pH of 4.5 to 8.4 (mean of 28 cases = 6.4) (Duke, 1978, 1979). Rhodesgrass is suitable and adaptable to tropical and subtropical summer-rainfall areas with rainfall of 7.5–12.5 dm annually, and a moderately long dry season. It does not thrive in areas with more than 18 dm rainfall. Thrives on soda-rich alkaline soils too alkaline for sugarcane. Adaptable to sands and alkaline clays, but grows best on fertile soils of medium texture. It is moderately frost-resistant, but unsuited to areas with more than an occasional heavy frost. Often forms almost pure stands (Reed, 1976).

Cultivation

Plants seed freely but also spread by stolons. However, it is easily controlled and seldom becomes a troublesome weed. Good land preparation is necessary to insure stands, maximum yields and minimum weed competition. Crop may be propagated by seeding, at rate of 8–9 kg/ha broadcast or 2–3 kg/ha sown in drills 50–70 cm apart. Drilled seed should be mixed with a carrier, such as rice hulls or sawdust, or mixed with fertilizer and sown with combine drill. Row spacing should be such as to permit rapid formation of a complete ground cover. Also propagated by rootstocks, between 25,000 and 37,500 stools/ha required, planted 45–60 cm each way. May be planted anytime during year, but February gives good results in the Puniab. Elsewhere, practice is to plant at onset of fall wet season to insure good survival, rapid growth and complete ground cover. Rhodesgrass may be planted with various legumes or other grasses. Combines well with lucerne at rate of 0.5–1.5 kg/ha; with Phasey bean (Macroptylium lathyroides) at rate of 1–2 kg/ha, or Bur Medick (Medicago tribuloides), or may be sown between rows of pigeon pea or Leucaena. Sometimes mixed with the more slow-growing Paspalum dilatatum to give rapid growth. Successfully established by drilling or broadcasting between rows of corn, cotton, or sorghum. In Queensland, Sudan-grass and white panicum are also used as companion crops for summer sowing. Light sowing of oats or wheat provides protection for winter sowing. It also does well under irrigation, as in California and Israel, where it grows on soils unsuitable for other grasses (Reed, 1976).

Harvesting

New stands should be allowed to flower and set seed before being grazed or mown. Rotational grazing is desirable, as continuous heavy grazing permits rapid invasion of weeds, especially on sandy soils. Hay should be cut at early flowering stage, with 7–8 cuttings per year (Reed, l976).

Yields and Economics

Crops yield 11.5–17.2 MT/ha DM annually, with even higher yields reported when planted in 25 cm rows and fertilized with 150 kg N/ha. Seed yields range from 65 to 650 kg/ha (Reed, 1976). In Saudi Arabia, Rhodesgrass gave the best yields (12.3 MT/ha) of ten grasses studied, with more uniform establishment and best winter growth (Farnsworth, 1977). Principle value of this warm-season pasture and hay grass lies in the ease and low cost of establishment and management, tolerance to wide range of soil types, moisture, and pH, and its ability to provide a sustained production of palatable forage throughout recurrent dry seasons or in the drier areas in the Tropics. Widely used for these purposes in the regions mentioned above (Reed, 1976).

Energy

According to the phytomass files (Duke, 1981b), annual productivity ranges from 2 to 20 MT/ha; 7 MT in Egypt, 2–6 MT in South Africa, 6–12 in Australla, 3–8 in Zambia, 4–12 in Fiji, 16–20 in Thailand, 8–19 in Cula. In Israel, the plant is sometimes grown with sewage irrigation, fertilized plots averaging 12 MT/ha DM from 5 cuts (Vaisman et al, 1980). It is perhaps the most suitable of all tropical cultivated grasses for saline soils (Bogdan, 1968).

Biotic Factors

Following fungi have been reported on Rhodesgrass: Aspergillus flavus, Cerebella andropogonis, Cladosporium sp., Claviceps sp., Cochliobolus heterostrophus, Fusarium equiseti, F. oxysporum, Helminthosporium carbonum, Himaydis sp., Nigrospora sphaerica, Puccinia chlorides, Pythium aphanidermatum, Tolyposporium chlorides, Trichoderma sp., and Uromyces kenyensis. Striga lutea and S. asiatica parasitize this plant. Nematodes isolated from Rhodesgrass include: Helicotylenchus dihystera, H. nannus, H. pseudorobustus, H. cavenessi, Hemicycliphora truncata, Hoplolaimus pararobustus, Meliodognye acronea, M. incognita acrita, M. javanica, Pratylenchus brachyurus, Rotylenchulus reniformis, Scutellonema clathricaudatum, Trichodorus minor, Tylenchus spiralis, Xiphinema elongatum, X. ifacolum. Insect pests include Fall armyworm (Spodoptera frugiperda) and caterpillars of Mocis latipes, both easily controlled by insecticides.

References

Complete list of references for Duke, Handbook of Energy Crops
Last update Tuesday, December 30, 1997