Dichanthium annulatum (Forssk.) Stapf

Subordinate taxon :
Dichanthium annulatum (Forssk.) Stapf var. papillosum (Hochst. ex A. Rich.) de Wet & J.R. Harlan

Andropogon annulatus Forssk.
Andropogon papillosus Hochst. ex A. Rich.
Dichanthium nodosum Willemet
Dichanthium papillosum (Hochst. ex A. Rich.) Stapf

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

bluestem, diaz bluestem, hindi grass, sheda grass, ringed dichanthium, (English);  lindi (Philippines);  marvel grass, karad, jargu grass, delhi grass (India);  vuda blue grass, kleberg blue-stem (USA);  pitilla (Cuba);  climacuna (Colombia);  song tha'o to (Vietnam);  ya hindi, ya waen (Thailand);  two-flowered golden-beard (Hong Kong).

Perennial tussock, sometimes stoloniferous, with culms geniculately ascending, foliage to 80 cm and fertile tillers to about 1 m (rarely 1.8 m);  pronounced annulus of radiating, 3-5 mm long white hairs on the nodes;  leaf blade linear, to about 30 cm long and 2-7 mm wide, margins sparsely pubescent and scaberulous.  Inflorescence a sub-digitate panicle, comprising 2-9 (-15) pale green or purplish racemes, each 3-7 cm long;  geniculate, twisted awn 8-25 mm long arising from the upper lemma of the sessile spikelet.  Caryopsis oblong to obovate, dorsally compressed, ca. 2 mm long (1.9 million/kg), although seed weight (sessile + pedicellate spikelet ) about 500,000/kg.  Surface rooted, >90% of roots in top 1 m soil.
Distinguished from D. caricosum in having nodal annulus , and from D. aristatum in lacking the short, dense pubescence on the peduncle immediately below the lowest raceme .

Native to:
Africa:  Kenya, Tanzania, Uganda, Ethiopia, Somalia, Algeria, Egypt, Libya, Morocco, Tunisia, Botswana, Namibia, South Africa, Mali, Senegal, Cape Verde.
Asia:  Afghanistan, Iran, Iraq, Israel, Jordan, Turkey (south), Bahrain, Saudi Arabia, Indochina, southern China, Myanmar, Thailand, Indonesia, Malaysia, India, Nepal, Pakistan.
Other:  Papua New Guinea.

Naturalised in:
Northern Australia and the Americas.  Found in situations ranging from dry to moist subtropics and tropics growing in pasture land, roadsides, fallow fields, weedy lawns, sand dunes and open wasteland.

Perennial pasture for grazing or cut-and-carry.  Suitable for silage and hay if cut before flowering.  Shows promise for re-seeding degraded grasslands and for rough lawns.

Adapted to most textures of soil from coralline sands to heavy black clays (cotton soils).  Not fertility demanding, but often found on fertile soils.  Prefers neutral to alkaline conditions, occasionally down to pH 5.5.  Tolerates poor drainage, but not permanently waterlogged situations.  Tolerant of salinity.

Mostly in moderately dry to moist areas with annual summer rainfall from 700-1,400 mm, but to as low as 300 mm and as high as 2,600 mm, sometimes with a 6-8 month dry season.

Good warm season growth.  Cut by frosts, but recovers with onset of warm conditions.  Occurs naturally at altitudes from sea level to >600 m asl .

Not considered shade tolerant.

Flowers throughout the growing season .

Stands very heavy grazing, forming an open turf.

Withstands seasonal burning.

Guidelines for the establishment and management of sown pastures.

Can be established vegetatively from rooted slips, being planted 60 cm apart in staggered rows 60 cm apart.  Commercial seed is rarely available.  Optimum temperature for germination is 32°C, although germination can be achieved between 15 and 40°C.

Not normally fertilised but responds to low to moderate levels of nitrogen.

Competes aggressively once established, often suppressing other species.

Grasses:  Bothriochloa insculpta , Dichanthium aristatum , D. caricosum .
Legumes:  Desmanthus spp., Medicago sativa , Stylosanthes hamata , S. seabrana .

Although many fungi have been reported on this grass , none seems to cause major damage - Balansia sclerotica, Cerebella andropogonis, Chaetostroma atrum, Cochliobolus cymbopogonis, Curvularia andropogonis, C. lunata, C. robusta, Ellisiella caudata, Jamesdicksonia obesa, Phyllachora ischaemi (tar spot), Physoderma dichanthicola, Pithomyces graminicola, Puccinia cesatii, P. duthiae, P. propinqua, Sclerospora dichanthicola, Sphacelotheca annulata, S. andropogonis-annulati, Tolyposporella obesa, Uredo susica, Uromyces andropogonis-annulati, U. clignyi and Ustilago duthiei.  It also parasitised by Striga lutea.  Ergot (Claviceps sp.) may present a significant seed production impediment in at least some accessions.

Although some types are stoloniferous , spread is mainly by seed, usually requiring some disturbance, e.g. cultivation, roadside mowing or grading.

Not a serious weed of cultivation or environment.

Crude protein levels are usually low ranging from 2.6-10.4% (mostly 4-6%), largely reflecting the low nitrogen status of the soil.  CP digestibility from 28-47%.

Readily eaten by small and large ruminants.

No problems reported.

Mostly of the order of 2-6 t/ha DM, although up to 17 t DM when irrigated grass in dry environment.

Can support up to 7 sheep/ha in semi-arid environment.

2n = 20, 40, 60.  Pseudogamous apomict , with varying levels of sexual reproduction.  Diploids may be completely sexual.  Tetraploids (2n = 40) most common in main area of distribution, but diploids have also been found in India.  Plants are hexaploid in southeast Africa.  Indian tetraploids cross relatively easily, and crosses with D. aristatum and D. caricosum (2n = 40) have been obtained.

Can be harvested either by direct heading, or swathing and feeding through the header, 2 harvests per year being possible, one in early to mid-summer, and the other in autumn.  Hand harvesting is laborious and expensive.

Susceptible to glyphosate.

• Tolerant of poor drainage.
• Tolerant of salt.
• Withstands heavy grazing.
• Drought-hardy.

• Relatively low production.
• Restricted to alkaline (or near neutral) soils.
• Relatively low quality.
• Fluffy seed difficult to sow.

Bogdan, A.V. (1977) Tropical Pasture and Fodder Plants (Grasses and Legumes). pp. 106-107. (Longman: London and New York). Coleman, S.W., Taliaferro, C.M., Tyrl, R.J. 2004. Old World Bluestems. (Warm Season Grasses) pp. 909-936.

Manidool, C. (1992) Dichanthium annulatum (Forssk.) Stapf. In: 't Mannetje, L. and Jones, R.M. (eds) Plant Resources of South-East Asia No. 4. Forages. pp. 181-183. (Pudoc Scientific Publishers, Wageningen, the Netherlands).

Mehra, K.L., Celarier, R.P. and Harlan, J.R. (1960) Effects of environment on selected morphological characters in the Dichanthium annulatum complex. Proceedings of the Oklahoma Academy of Science, 40, 10-14.

http://www.fao.org/ag/AGP/AGPC/doc/Gbase/data/pf000213.htm
http://www.fao.org/ag/aga/agap/frg/afris/Data/68.HTM
http://www.hear.org/pier/species/dichanthium_annulatum.htm
http://www.hort.purdue.edu/newcrop/duke_energy/Dichanthium_annulatum.html

Cultivars	Country/date released	Details
'Kleberg'	USA (1944)	Naturalised strain from King Ranch, Texas.  Slender stems growing to 75 cm at maturity.  Excellent drought tolerance, good seed producer, some salinity tolerance, relished by cattle.  Performs well on sandy clay loam and clay loam sites in the >625 mm rainfall areas of southern Texas.
'Pretoria 90' (PI 188926, BN-6730, T-20090)	USA (1954)	Selected for seedling vigour, rapid growth, yield.  Stems to 1.5 m at maturity.  Little stolon development.  Good drought tolerance, leafy;   used for pasture, hay and silage .  Low seed production.  Commercial seed no longer produced in Texas.
'T 587', 'PMT-587'	USA (1981)	Derived from a composite of 80 accessions, mostly Dichanthium, initially established in the 1950s.  The mixture originally also contained D. aristatum , Bothriochloa bladhii and B. insculpta , although some accessions have been lost with time.  Suitable for pasture, hay, revegetation of disturbed areas and salt scalds, erosion control, and range reseeding.  More cold tolerant than 'Gordo', 'Medio', and 'Kleberg'.  Leafier than 'King Ranch', leaves longer and wider.  Resistant to leaf rust.  High forage producer.  Grows from late winter/early spring through late fall.  Performs well on sandy clay loam and clay loam sites in the >625 mm rainfall areas of southern Texas.
'Marvel 8' (CPI 106073)	India	40-100% better DM yields than local strain.

Promising accessions	Country	Details
IGFRI-S-495-1, IGFRI-S-495-5	India	Lines selected at Indian Grassland and Fodder Research Institute, Jhansi, Uttar Pradesh.
CPI 84146B	Queensland, Australia	Institutional collection from Rahuri, Andhra Pradesh, India.  Ergot susceptible;  more productive than naturalised ecotype in central Queensland.