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Graminae
Synonyms
Andropogon annulatus (Forsk.).
Common names
Sheda grass (Australia), lindi (the Philippines), karad, marvel
grass, Delhi grass (India), Kleberg blue-stem (United States), pitilla
(Cuba).
Description
Tufted perennial to 60 cm; the nodes bearded; leaves papillose-pilose
at least on the upper surface; first glume of the sessile spikelet not
indurate, or slightly indurate. Two to six racemes, sometimes more. Lower
glume of sessile spikelet with tubercle-based hairs toward the tip (Tothill
& Hacker, 1973), oblong, obtuse or truncate, keel not winged. Median
nerve present, sheaths terete, ligule longish (Bor, 1960). It differs from
D. caricosum in having the first glume keeled, not winged, a medial nerve,
and large membranous ligule (Dabadghao & Shankarnarayan, 1973). Ninety-six
percent of its roots end within a depth of 1 m. It differs from Bothriochloa
pertusa in having no pitting on the glumes (Narayanan & Dabadghao,
1972) and from Dichanthium sericeum by the spikelets having a naked appearance
due to the hairs being few or almost absent. The spikelets are also very
blunt at the top (White, personal communication). Roots penetrate to 100
cm in alluvial soil at Varanasi, India, with a yield of 11 275 kg/ha of
oven-dried roots (Ramam, 1970).¤
Distribution
Tropical Africa to Southeast Asia, New Guinea and northern
Australia.
Altitude range
It has a range of 250-1 375 m in India.
Rainfall requirements
Tropical and subtropical rainfall patterns. It is found mostly
in India in the 500-900 mm rainfall regime (Dabadghao & Shankarnarayan,
1973). It persisted poorly in arid zone trials at Alice Springs, Australia
(Millington & Winkworth, 1970). The strain was from India.
Drought tolerance
It evades or endures drought well (Whyte, 1968).
Soil requirements
It tolerates a wide range of soils but prefers black cotton
soils in India and will not thrive in acidic soils.
Ability to spread naturally
Good.
Land preparation for establishment
A good seed-bed is required for early establishment, but it
will gradually colonize a rough seed-bed.
Sowing methods
Usually established from root slips in India, as seed collection
is laborious and expensive. It is sown in rows 60 cm apart with a similar
distance between the plants, as they form large tussocks.
Sowing time and rate
Sow at the commencement of the wet season.
Response to defoliation
It forms an open turf under grazing and stands very heavy grazing
(Dabadghao & Shankarnarayan, 1973).
Grazing management
It is not usually managed, but, if overgrazed, a Dichanthium-
Iseilema grassland in Bellary, Mysore, India deteriorates first to Bothriochloa
sp., then Eremopogon sp. and Andropogon sp. and finally to an inferior
Aristida sp./Andropogon sp./Eragrostis sp. sward (Chinnamani, 1968). Green-matter
production fell from 6 000-10 000 kg/ha with Dichanthium-Iseilema to 200-1
500 kg/ha with the poor Aristida/Andropogon/Eragrostis association.
Dry-matter and green-matter
yields
At Bellary, Mysore, India, on black cotton soils a mixture
of D. annulatum and Iseilema anthephoroides yields 6 000-10 000 kg/ha of
green herbage (Chinnamani, 1968). An average hay production of 3 300 kg/ha
can be expected from a good D. annulatum stand (Dabadghao & Shankarnarayan,
1973; Srinivasan, Bonde & Tejwani, 1962).G
Suitability for hay and
silage
It is widely used for hay in India (Narayanan & Dabadghao,
1972).
Cultivars
In Maharashtra State, India, Oke (1971) recommends 'Marvel
8', a strain which gives 40-100 percent better yields of dry matter than
the local strain, while Chakravarty and Kackar (1971) selected Nos. 485,
487 and 490, selections which produced annual mean yields in the 1965-69
seasons of 1 450, 2 010 and 1 760 kg DM/ha respectively. There are two
varieties in Queensland: var. grandispiculatum, which is taller and more
robust than the main type, and var. monostachym, which differs in having
a single spike to the seed-head in place of the usual several.
Main attributes
Its wide adaptability, tolerance of alkaline soils and its
effective erosion control.
Main deficiencies
Its variability and its dominance of other grasses.
Minimum temperature for
growth
In Bihar, India, it produced 3 214 kg/ha in summer and 367
kg/ha in winter with a dressing of 44 kg N and 34 kg P2O5/ha per year (Singh
& Chatterjee, 1968). There was some winter greenness.
Latitudinal limits
8-28°N in India.
Palatability
Good. Preferred to Cenchrus ciliaris in India.
Tolerance to flooding
It survives short-term flooding.
Fertilizer requirements
In India, the application of 22.75 kg N/ha to a natural pasture
of predominantly D. annulatum increased the content of D. annulatum and
decreased Heteropogon contortus and Eremopogon (Erasmus & Sud, 1976).
Compatibility with other
grasses and legumes
It does not grow well in mixtures as it crowds out other grasses.
Genetics and reproduction
2n=20, 40, 60 (Fedorov, 1974). It is quite a variable species.
Seed production and harvesting
It seeds heavily and in India seeds are hand collected.
Economics
On the black cotton soils of Bellary, Mysore, India, it is
a climax species with Iseilema anthephoroides and is a palatable and nutritious
species (Chinnamani, 1968). It is a climax species along with Sehima nervosum
over practically the whole of peninsular India and one of the most important
grasses in the Dichanthium/Cenchrus/Lasiurus cover in semi-arid northern
India (Dabadghao & Shankarnarayan, 1973). It is widely used in the
Philippines for pasture improvement.
Animal production
In the Rajasthan desert area of India, D. annulatum has supported
6.93 sheep per hectare at Pali (Des, 1973).
Further reading
Harlan et al., 1961; Whyte, 1964.
Dormancy
In India, Leelavathy (1969) found the filtrate of the rhizosphere
fungus Trichoderma viride reduced the germination of D. annulatum seed
from 90 to 77 percent.
Value for erosion control
Of numerous grasses tested by Srinivasan, Bonde and Tejwani
(1962) for stabilizing the bunds in the ravine lands of Gujarat, India,
D. annulatum proved one of the best because of its elaborate root system
and excellent ground cover. It has also proved useful for erosion control
on 20° slopes (Misra, Ambasht & Singh, 1977).G
Tolerance to salinity
It tolerates saline soils well and occurs on such soils in
India in association with Sporobolus marginatus.
Growth rhythm
It grows during the wet season from June to November in India
and after harvest in November for hay. It provides spring growth from February
to March, but this growth is stemmy (Dabadghao & Shankarnarayan, 1973).
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