Dichanthium annulatum (Forsk.) Stapf.
Diaz bluestem, Marvel
Source: James A. Duke. 1983. Handbook of Energy Crops. unpublished.
- Folk Medicine
- Yields and Economics
- Biotic Factors
Highly esteemed as fodder grass, especially in India, where it is eagerly eaten
by cattle. It is fed green, when it is young, and when in flower; also
suitable for silage and.hay if cut before flowering. Shows promise for
reseeding degraded grasslands; also used for rough lawns.
No data available.
Per 100 g, the wet matter (25.0% DM) is reported to contain (ZMB) 10.4 g
protein, 1.7 g fat, 75.8 g total carbohydrate, 34.9 g fiber, 12.1 g ash, 1.7 g
EE, and 40.9 NFE (Gohl, 1981). Per 100 g, the hay is reported to contain (ZMB):
2.7 g protein, 1.2 g fat, 84.6 g total carbohydrates, 39.1 g fiber, 11.5 g ash,
1.2 g EE, and 45.4 g NFE (Gohl, 1981).
A highly variable perennial grass, forming dense tufts, with erect culms up to
1 m tall from a decumbent base, nodes pubescent; blades flat, 5-20 cm long,
tapering to a fine point, inflorescence of subdigitately arranged racemes,
these 3-6, sometimes more [var. bladhii (Retz.) Hack.], 3-7 cm long; not
more than 3 pairs of the lowest spikelets sterile; peduncle of raceme glabrous;
sessile and pedicellate spikelets alike, usually overlapping, the pedicels
usually in part visible; lower glumes of pedicellate spikelets not armed with
marginal bulbous-based bristles; lower glume of sessile spikelet oblong, obtuse
or truncate, keel not winged, median vein present; sheaths terete; ligule
longish; upper lemma the hyaline base of the awn.
Reported from the, African & Hindustani Centers of Diversity, diaz bluestem
or cvs thereof is reported to tolerate drought, fire, high ph, salt, poor soil,
and sand. In India it occurs in a great variety of forms, Pseudogamous
apomict. Tetraploids with chromosome number 2n = 40 prevail in the main
area of its distribution, but diploids have also been found in India. In S.E.
Africa, plants are hexaploids. Diploid races of India are genetically isolated
but tetraploids cross relatively easily and crosses with D. aristatum
and D. caricosum have been obtained (Bogdan, 1977). (2n = 40)
Common throughout the plains and hills of India up to 1660 m; also in tropical
and North Africa extending east through Southeast Asia to China, Australia,
Fiji and New Guinea. Introduced to West Indies (Cuba, Haiti, and Puerto Rico).
Ranging from Subtropical Dry to Moist through Tropical Very Dry to Dry Forest
Life Zones, Diaz bluestem is reported to tolerate annual precipitation of 7.0
to 26.4 dm (mean of 6 cases = 12.3) annual temperature of 12.5 to 27.5°C
(mean of 6 cases = 21.6) and pH of 5.5 to 7.8 (mean of 6 cases = 6.7). Found
naturally in weedy lawns, sand dunes, fallow fields, roadsides, open wasteland,
in hedges and pastures; often escaping and becoming weedy. Thrives in
sheltered and disturbed areas, neglected areas near crop fields, and in grass
fields where it tends to be a grass weed. Adapted to tropical and subtropical
summer rainfall areas. Quite drought-resistant, and tolerates seasonal burning.
Propagated by seed. Plants are good seed producers but show great variability
in their ability to germinate. Usually the very light seeds are spread by
wind, allowing invasion of new areas. Experiments indicate that seeds produced
by plants from protected areas give maximum germination of 95.3%, whereas those
from shady areas give 84.6% and those from grazed fields, 36%. Seeds with
glumes intact give 56.6% germination, and those with glumes removed give 94.6%.
Due to glume removal, the embryo becomes exposed directly to light and
moisture, causing higher germination. Also increased depth of planting of seed
lowers the germination percentage. Seed germinates at a temperature range of 15-40°C; optimum, temperature for germination being 32°C (up to 78%). Seeds preheated to a sub-freezing temperature of -10°C for 15 days germinate 78.6% at room temperature (27°C +/-5°). Periodic tillering from the underground rhizome maintains the perennial habit of this grass. Forms open turf under grazing.
Cut before flowering, for use as hay and silage.
Dichanthuium. annulatum is regarded as one of the best pasture grasses
in India and Burma, although the CP content of herbage is usually low to
medium. Used extensively throughout the range of Southeast Asia and the East
Indies. Sometimes used in the West Indies as well, especially for rough lawns.
In India unclipped plots yield 8925 Kg/ha compared with 3225-3570 for clipped
plots. (Gupta, 1980)
According to the phytomass files (Duke, 1981b) , annual productivity ranges
from 7 to 17 MT/ha. Diaz bluestem yields more than 10 MThay/ha, and stands
cutting well (Reed, 1976); Duke (1978) reports 8 MT hay/ha. Herbage in India,
depending on soil moisture yields 2-20 MT/ha; in a semi-arid area in Cuba - 17
MT DM/ha (46% of yield from dry season with sprinkler irrigation); in India,
'Marvel 8' yielded 25 MT green fodder/ha under irrigation and 12 MT under dry
land conditions (Bogdan, 1977).
The following fungi have been reported on this grass; Balansia sclerotica,
Chaetostroma atrum, Curvularia andropogonis, C. lunata, Ellisiella caudata,
Jamesdicksonia obesa, Physoderma dichanthicola, Puccinia cesatii, P. duthiae P.
propinqua, Sclerospora dichanthicola, Sphacelotheca annulata, S.
andropogonis-annulati, Tolyposporella obesa. Uredo susica, Uromyces
andropogonis-annulati, U. clygni, Ustilago duthiei. It also parasitized
by Striga lutea.
Complete list of references for Duke, Handbook of Energy Crops
- Bogdan, A.V. 1977. Tropical pasture and fodder plants. Longman, London.
- 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.
- 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.
- Gohl, B. 1981. Tropical feeds. Feed information summaries and nutritive values.
FAO Animal Production and Health Series 12. FAO, Rome.
- Gupta, S.K. 1980. Effect of clipping on biomass and net productivity of
underground parts in grassland ecosystem. Indian J. Ecol. 7(2):215-223.
- Reed, C.F. 1976. Information summaries on 1000 economic plants. Typescripts
submitted to the USDA.
last update July 10, 1996