Ischaemum ciliare


Scientific name

Synonyms

Ischaemum aristatum auct., non L.
Ischaemum ciliare subvar. villosum (Nees) Hack.
Ischaemum indicum auct., non (Houtt.) Merr.
Spodiopogon villosus Nees

Family/tribe

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

Common names

batiki bluegrass, (m)balanga grass (Fiji);  indian murainagrass (North America);  smutgrass (English);  pasto ratana (rattana, rotana) (Spanish);  blemblem, rumput padang (Indonesia);  rumput gerek telinga (Malaysia);  ya wai, ya-yonhu (Thailand);  toto grass (Surinam);  mom an (Vietnam).

Morphological description

A tufted or spreading stoloniferous perennial, rooting freely at the lower nodes, and forming a dense mat under regular defoliation.  Culms erect or geniculate, often branching, mostly to 0.9 (rarely 1.3) m tall, nodes bearded.  Leaves grey green sometimes with purple-coloured margins;  leaf sheath often tight, hairy around the node, otherwise sparsely hairy to glabrousligule membranous, truncate, 1–2 mm long;  leaf blade narrowly lanceolate, 5–30 (–60) cm long and 0.3–1 (–2) cm wide, acuminate at apex, usually sparsely to densely hairy.  Inflorescence well exserted, comprising 1 or 2 terminal racemes 2–10 cm long, breaking up at maturity;  spikelets bisexual, 3–5 mm long with twisted geniculate awn 8–15 mm long, paired (one sessile, one pedicellate), spikelet pairs inserted alternately along the flattened triangular rachis.  c. 600,000 seed units/kg (1 seed unit = sessile spikelet + pedicellate spikelet< /A > + awns).

Distribution

Native to:
Asia:  Bangladesh, China, India, Malaysia (peninsular), Myanmar, Sri Lanka, Taiwan, Thailand, Vietnam.
Found in open, grassy glades in lowland forests, roadsides, ditch banks, pond margins, and lawns.

Naturalised in:
West Africa, tropical America and the Pacific Islands.

Uses/applications

Permanent pasture and good ground cover with rapid spread from cuttings giving good competition against annual weeds after soil disturbance or clearing of forest.  Often used as a turf.  Moderate but stable production on poor soils on sloping land.  Could be used for cut-and-carry.

Ecology

Soil requirements

Adapted across a wide range of soil textures (except on sandy or coralline soils), fertility levels and soil reactionpH (4.5–) 5.5–7 (–8).  It is especially useful on very acid, low fertility soils with high Al, and can tolerate poor drainage and some salinity.

Moisture

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Although a variable species and sometimes found in seasonally dry monsoonal regions, I. ciliare has greatest application in the wet tropics with up to 7,000 mm rainfall.  It is not drought tolerant, but has good flood tolerance.

Temperature

I. ciliare grows best in the lowland tropics, although it extends to >600 m asl in Costa Rica and Western Samoa.  It is unproductive in cooler environments, having an optimum growing temperature between 30 and 35ºC and no frost tolerance .

Light

It is moderately shade tolerant remaining productive and persistent with light transmission as low as 40%, performing well under coconuts.

Reproductive development

Flowering response is variable, with reports of flowering throughout the year in Malaysia (near the equator), in June-July in Thailand, and in July-August and January-February in India (both north of the equator), and April-May in Fiji (south of the equator).

Defoliation

Requires regular defoliation since quality declines rapidly with age of regrowth.  It is very tolerant of heavy grazing.  Generally effective as a weed suppressant.  However, constant heavy grazing may allow invasion of annual weeds and aggressive perennial species such as navua sedge (Cyperus aromaticus/Kyllinga polyphylla).

Fire

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Not usually relevant in high rainfall areas.

Agronomy

Establishment

Normally established vegetatively to achieve rapid ground cover and weed suppression, and because seed production is unreliable.  Cuttings can be broadcast onto the soil surface and disced in, or planted on a 30 cm grid.  Seed shows dormancy for up to 6 months after harvest, with germination continuing to improve for up to 10 months under good storage conditions.  Seedlings are vigorous.

Fertiliser

Competes with associated coconuts (Cocos nucifera) for N and P.  Responds to low levels of applied N, but response declines with increasing levels, from 16 kg DM/kg N at 75 kg/ha N, to 7 kg DM/kg N at 225 kg/ha N.  CP levels increase with increasing rates of N.  Responses to P have been measured in associated legumes, but not in the grass .

Compatibility (with other species)

I. ciliare is a competitive grass , suppressing most associated species, although forming stable mixtures with some legumes.  Very effective in suppression of weedy species, Hyptis capitata and Chromolaena odorata, but not Cyperus aromaticus/Kyllinga polyphylla.

Companion species

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Grasses:  May be grown in similar conditions to the more aggressive and productive Brachiaria humidicola and Hemarthria altissima .
Legumes:  Desmodium heterophyllum , D. triflorum and Mimosa pudica.

Pests and diseases

In Asia and Papua New Guinea, flowers can be infected with a smut (Sphacelotheca ischaemicola), which causes failure of inflorescence to emerge.  In Costa Rica, productivity in periods of high rainfall is reduced by attack by Aenolamia sp. (Homoptera: Cercopidae).  Leaf blotch is commonly seen on leaves during wet weather.

Ability to spread

Rapid local spread through stolons, pieces of which may be transferred between cloven hooves.  Seed does not spread by wind.

Weed potential

Ability to spread through long stolons can make it a weed of cultivated land.  Not considered to be an environmental invasive by the Pacific Island Ecosystems at Risk (PIER) group.

Feeding value

Nutritive value

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Soft leaf of reasonable nutritional value but likely to be limited on low fertility soils.  CP values range from 18% in 10-day regrowth, to 14% at 3 weeks, 11% at 6 weeks, 8% at 8 weeks, and 6% or below in mature foliage.  Average IVDMD of 5-week regrowth measured at 59%.

Palatability/acceptability

Palatable and readily eaten.

Toxicity

No reports of toxicity, but suspected of causing milk taint.

Production potential

Dry matter

Reported dry matter yields range from 3–20 (–27) t/ha DM.  Usually harvested by grazing animals but capable of about 10 t/ha DM under high rainfall .

Animal production

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Liveweight gains of 0.4–0.5 kg/head/day have been recorded during the growing season , but in cooler/drier periods, productivity may fall to below zero.  Milk production is poor, and even with supplements, only 6–7 kg/head/day is achieved with 3–4 cows/ha.  Higher productivity is achieved with more rapid grazing rotation.

Genetics/breeding

2n = 36 or 72.

Seed production

Seed set is unreliable, and harvesting and drying tend to be difficult under high rainfall conditions.  Smut fungus can have a significant effect on potential seed yields.  Seed storage also presents problems in the hot, humid environments where I. ciliare is mostly grown.

Herbicide effects

No information available.

Strengths

  • Palatable.
  • Tolerant of heavy grazing.
  • Adapted to acid, low fertility soils.
  • Tolerant of waterlogging .
  • Good ground cover/weed suppression.

Limitations

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  • Low to moderate productivity.
  • Mediocre quality.
  • Poor drought tolerance.
  • No cold tolerance.

Other comments

  

Selected references

Arosemena, E., Pezo, D.A., Kass, D.L. and Argel, P.J. (1996) Requerimientos externos de fÓsforo en pasto ratana (Ischaemum indicum (Houtt.) Merrill) y Brachiaria brizantha (A. Rich.) Stapf. Pasturas Tropicales, 18, 34–40.
Baki, B.B., Ipor, I.B. and Manidool, C. (1992) Ischaemum ciliare Retzius. In: 't Mannetje, L. and Jones, R.M. (eds) Plant Resources of South-East Asia No. 4. Forages. pp. 142–144. (Pudoc Scientific Publishers, Wageningen, the Netherlands).
Gilliland, H.B., Holttum, R.E. and Bor, N.L. (1971) A Revised Flora of Malaya Volume III Grasses of Malaya. (The Botanic Gardens: Singapore).

Internet links

Cultivars

Cultivars

Country/date released

Details

None released to date.      

Promising accessions

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Promising accessions

Country

Details

None reported.