Urochloa mosambicensis


Scientific name

Synonyms

Brachiaria stolonifera Gooss.
Echinochloa notabile (Hook. f.) Rhind.
Panicum mosambicense Hack.
Urochloa pullulans Stapf, nom. illeg.
Urochloa stolonifera (Gooss.) Chippind.

Family/tribe

Family: Poaceae (alt. Gramineae) subfamily: Panicoideae tribe: Paniceae.

Common names

African liverseed grass, bosveldbeesgras, buffalo grass, buffelsgras, bushveld signal grass, bushveld herringbone grass, common urochloa, gewone urochloa, paper grass, witbuffelsgras (South Africa);  sabi grass (Australia);  capim-corrente (Brazil);  daly (Costa Rica);  gonya grass , mbawani, bumbunzwa, mpunga nini (Zimbabwe, Zambia);  tunga (Mozambique);  ya sabee (Thailand);  rumput sabi (Indonesia).

Morphological description

A perennial, loosely tufted grass sometimes rooting and branching from the lower nodes, variable in size and habit , occasionally with stolons, rarely rhizomes.  600,000–1 million seeds/kg.

There are three morphological types, based on former species:
Stolonifera type:  Sward-forming, stoloniferous, sometimes rhizomatous, and tufted with basal nodes swollen;  generally smaller than the mosambicensis type, with foliage mostly 10–30 cm, and culms 30–70 (–100) cm tall.  Leaf blades 40–130 mm long, 2–9 mm wide.  Early or late flowering, with panicle comprising 2–6 racemes, 10–60 mm long;  spikelets usually untidily arranged on rachis, 2.5–3 mm long, awn of upper lemma <0.5 mm long, lower glume without stiff hairs on the back.

Mosambicensis type:  Stoloniferous and tufted, sometimes rooting and branching from the lower nodes.  Culms (30–) 60–100 (–120) cm tall.  Basal leaf-sheaths glabrous or hairy, nodes usually hairy;  leaf blades usually hairy, 20–300 mm long, 3–20 mm wide.  Panicle comprising (2–) 3–15 racemes, 20–100 mm long;  spikelets mostly symmetrically arranged in 2 rows on the rachis, 3–5 mm long, awn on the upper lemma 0.5–1.2 mm long.  Distinguished from pullulans type in having a tubercle-based bristle in the middle of the lower lemma in the fresh state.

Pullulans type:  Tufted, often with robust stolons.  Taller than other types, with culms 90–130 (–150) cm.  Leaves glabrate .  Tends to flower late in the season, usually somewhat sparsely.

Another form within the complex, the rhodesiensis type, is small and low yielding, with little agronomic potential.

Distribution

Native to:
Africa:  Botswana, Kenya, Malawi, Mozambique, South Africa (Eastern Cape, Free State, Gauteng, KwaZulu-Natal, Limpopo, Mpumalanga, North West Province), Swaziland, Tanzania, Uganda, Zambia, Zimbabwe.
Usually found in wooded grassland and deciduous bushland, or on disturbed sites, especially where the soil is fertile.

Naturalised in:
Tropics and subtropics in USA (Hawaii, Texas), Australia (north), India, Sri Lanka, Myanmar, Thailand, Indonesia and Fiji.

Uses/applications

Mostly used for permanent pasture, but makes good hay .  It is effective for erosion control and other applications where rapid establishment and good ground cover are advantageous.

Ecology

Soil requirements

Stolonifera type:  Found on lighter textured soils from sands to clay loams, sometimes of calcareous origin, near rivers or pans, often in disturbed places.
Mosambicensis type:  Mostly occurs on sands and sandy loams, but also on clay loams and red clays.
Pullulans type:  Found on sands to clay loams, and less commonly, clays.
Collections have been made in soils with pH from 5.8–8.5, and available soil phosphorus levels as low as 5 ppm.  It has also become naturalised on soils with available P levels as low as 4 ppm .

Moisture

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Stolonifera type:  Mostly from 800–1,000 mm rainfall environments, with the exception of ‘Saraji’, which originates from an area receiving 500 mm/yr.
Mosambicensis type:  From 360–1,300 (mean 710) mm rainfall environments, usually on well-drained soils and does not tolerate flooding or waterlogging .
Pullulans type:  From 700–1,600 mm rainfall environments, and often on seasonally flooded soils.
In general, U. mosambicensis prefers well-drained soils and is drought tolerant.

Temperature

U. mosambicensis is mostly found from near sea level to 1,000 m asl, although the mosambicensis type has been collected at 1,500 m asl in Zimbabwe.
Stolonifera type:  Largely found between about 22 and 29ºS.
Mosambicensis type:  This diverse type encompasses a number of the morphological/agronomic groups proposed by various workers.  It is found over a similar range to that of the stolonifera type in southern Africa, and extends north to about 4ºS in Kenya.
Pullulans type:  Largely from more tropical environments between 3ºS in Tanzania and 16ºS in Malawi.
This is equivalent to a wide temperature range, from about 17–24ºC, and there may well be differences in temperature adaptation among accessions.  In general, U. mosambicensis can withstand high temperatures, and can produce some cool season growth if not checked by frost.

Light

Tolerant of light shade.

Reproductive development

Many genotypes are day neutral, although short day plants have been identified particularly in the pullulans type.  Day neutral types flower continuously from 3–4 weeks after the beginning of the wet season, or the commencement of growth after frost.  There appears to be an additional effect due to the influence of low temperatures.

Defoliation

All U. mosambicensis types are very grazing tolerant, with stolonifera types being particularly stable under heavy grazing or regular defoliation , forming low, dense swards.

Fire

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Recovers well from fire.

Agronomy

Establishment

This grass can be established by planting stolon pieces or slips, or sowing seed, usually at 2–4 kg/ha.  Seed remains dormant for 6–12 months after harvest, due to physical obstruction of the embryo by the enclosing lemma and palea.  Germination of fresh seed can be improved by removal of these glumes, this being achieved effectively by hammer-milling e.g. 2,400 rpm using a 4.75 mm mesh screen.  Seed can be broadcast onto the surface of a well-prepared seed-bed, or placed to a depth of 2 cm.  Seed can also be oversown onto undisturbed pasture, although it may take up to 4 years to achieve a good cover of sown grass .  Seedlings develop more rapidly than many other warm season grasses.

Fertiliser

Despite growing naturally on soils with low available phosphorus, large responses to applied P have been measured.  On very low fertility soils, applications of up to 35 kg/ha P may be necessary to maximise production.  A critical P level in the tissue of 0.2% of the DM is proposed.  It can also survive on low N soils by virtue of non-symbiotic nitrogen fixation in the rhizosphere .  However, it responds well to applied N.

Compatibility (with other species)

Combines well with legumes, although can dominate in the short term if well fertilised.  Good ground cover and rapid Urochloa seedling development contribute to suppression of annual weeds.

Companion species

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Pests and diseases

U. mosambicensis is not subject to major diseases, and has no major pests, although aphids have caused problems in seed crops of ‘Saraji’.  It is a host for a number of viruses, including Maize Dwarf Mosaic Virus (MDMV), which also infects Zea mays and Pennisetum glaucum , and Sugarcane Mosaic Potyvirus and Barley Yellow Dwarf Luteovirus.

Ability to spread

Stoloniferous forms spread locally by stolons, and free-seeding types disseminate widely as shown by extensive naturalisation.

Weed potential

Although listed in some weed lists, it is too palatable and insufficiently aggressive to become a serious weed.

Feeding value

Nutritive value

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Protein levels, IVDMD and other measures of nutritive value vary with age of regrowth and soil fertilityCP levels in immature growth of fertilised grass can approach 20%, and IVDMD 65–70%.  These values may decline to less than 10% CP and 40–50% IVDMD in mature material.  Phosphorus levels in young grass on infertile soil are a little over 0.1%, but can rise to 0.6 or more if heavily P fertilised.  Sodium levels in stolonifera type material has been measured at 0.6–1.5%, and in mosambicensis type at 0.1–0.9%.

Palatability/acceptability

Livestock selectively graze U. mosambicensis when it is young, and still find it more palatable than many other warm-season grasses when mature.

Toxicity

No toxicity has been recorded.

Production potential

Dry matter

DM yields vary markedly with rainfall , and N and P fertility.  Generally, DM yields are in the range of 1–8 t/ha, even with moderate applications of N.  Without superphosphate on low P soils, yields can be <0.5 t/ha DM, whereas with applied P, comparable yields of >5 t/ha DM have been measured.

Animal production

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When grown with Stylosanthes humilis in the seasonally dry tropics, ‘Nixon’ has produced live-weight gains of the order of 80–360 kg/ha/year, with stocking rate extremes of one beast to 0.4–1.6 ha.  Increased production at higher stocking rates reflect increasing legume proportions in the pasture .

Genetics/breeding

An aposporous apomict with various chromosome complements.
Stolonifera type:  no data.
Mosambicensis type:  2n = 28, 42.
Pullulans type:  2n = 28.
A chromosome number of 30 has also been reported.

Seed production

Three, and up to five harvests per season are possible with day neutral varieties, but only a single harvest from short-day varieties.  Seed is harvested by direct heading, producing seed yields of (80–) 100–190 (–220) kg/ha/harvest, and 300 kg/ha or more per year.

Herbicide effects

Controlled by glyphosate at normal rates.  Tolerates atrazine at 4 L/ha.

Strengths

  • Adapted to various soil types.
  • Establishes quickly.
  • Very palatable.
  • Tolerates heavy grazing.
  • Mostly good seed production.

Limitations

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  • Mostly does not grow on heavy clays.
  • Structure deteriorates rapidly with onset of dry season.

Other comments

  

Selected references

Burt, R.L., Sinclair, D.F., Harrison, P., Pengelly, B.C. and Williams, W.T. (1980) Preliminary agronomic evaluation of some perennial Urochloa species over a range of environments. Australian Journal of Experimental Agriculture and Animal Husbandry, 20, 439–446.
Burt, R.L., Williams, W.T., Gillard, P. and Pengelly, B.C. (1980) Variation within and between some perennial Urochloa species. Australian Journal of Botany, 28, 343–356.
Clayton, W.D. and Renvoize, S.A. (1982) Gramineae (Part 3). In: Polhill, R.M. (ed.) Flora of tropical East Africa A.A. Balkema on behalf of the East African Governments, Rotterdam, Netherlands.
Harwood, M.R., Hacker, J.B. and Mott, J.J. (1996) Urochloa mosambicensis : A grass with potential for coal mine revegetation in central Queensland. Tropical Grasslands, 30, 152.
Harwood M.R., Hacker, J.B. and Mott, J.J. (1999) Field evaluation of seven grasses for use in the revegetation of lands disturbed by coal mining in Central Queensland. Australian Journal of Experimental Agriculture, 39, 307–316.
McIvor, J.G. (1984) Effects of phosphorus and superphosphate on the growth of Urochloa species. Australian Journal Of Experimental Agriculture And Animal Husbandry, 24, 571–578.
McIvor, J.G. (1992) Urochloa mosambicensis (Hack.) Dandy. In: ’t Mannetje, L. and Jones, R.M. (eds) Plant Resources of South-East Asia No 4. Forages. pp. 230–231. (Pudoc Scientific Publishers, Wageningen, the Netherlands).
Pengelly, B.C.and Eagles, D.A. (1999) Agronomic variation in a collection of perennial Urochloa spp. and its relationship to site of collection. Genetic Resources Communication No. 29. CSIRO Tropical Agriculture, St Lucia, Qld Australia. ISBN 0 643 05912 1.
Whiteman, P.C. and Gillard, P. (1971) Species of Urochloa as pasture plants. Herbage Abstracts, 41, 351–357.

Internet links

Cultivars

Cultivars

Country/date released

Details

‘Nixon’
(CPI 6559)
Northern Territory, Australia (1973) Institutional collection from Sabi Valley, Zimbabwe.  A mosambicensis type, best adapted to tropical monsoon conditions with a rainfall of 600–1,200 mm and a dry season of 5–9 months.  Suitable for use on a wide range of soils from clay loams to sandy soils, but appears most suitable for the lighter soil types.  Not suitable for flooded sites.
‘Saraji’
(CPI 60128)
Queensland, Australia From Mpumalanga, South Africa (25ºS, 1,000 m asl, rainfall 500 mm).  Low growing (±40 cm) stolonifera type.  Selected for seedling survival and ground cover under conditions of below average rainfall.  Used for revegetation and stabilisation of moderately alkaline (pH 8) and saline mine (E.C. = 7.4 mS/cm) spoils.

Promising accessions

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Promising accessions

Country

Details

CPI 46876 Australia Institutional collection from Swaziland.  Robust mosambicensis type.  Consistently high-yielding across a range of tropical and subtropical sites.
CPI 46935 Australia Institutional collection from Ilonga Research Centre, Tanzania (500 m asl ).  Introduced as U. pullulansDecumbent growth habit, and high stolon density.  Very high dry matter yield.  Failed to flower at 27ºS, but did flower at 19ºS, although somewhat sparsely.
CPI 47037 Australia Institutional collection from Mlingano Research Station, Tanzania.  Introduced as U. pullulans.
CPI 60147 Australia From Mozambique (16ºS, 600 m asl, rainfall 1,600 mm).  Introduced as U. pullulans.
The group below have all been identified as having an outstanding combination of high dry matter yield, stolon number and stolon length.
CPI 60115 Australia From Balantyre, Malawi (16ºS, 60 m asl, rainfall 700 mm).  Pullulans type.
CPI 60132 Australia From Same, Tanzania (04ºS, 700 m asl, rainfall 750 mm).  Pullulans type.
CPI 60144 Australia From Morogoro, Tanzania (07ºS, 700 m asl, rainfall 800 mm).  Pullulans type.
CPI 60148 Australia From Beira, Moçambique (20ºS, 45 m asl, rainfall 1,200 mm).  Mosambicensis type.
CPI 60159 Australia From Bihari Beach, Tanzania (07ºS, 45 m asl, rainfall 1,100 mm).  Pullulans type.
CPI 115793 Australia From Chinhoyi, Zimbabwe (17ºS, 1,120 m asl, rainfall 820 mm).  Mosambicensis type.