Amaranthus dubius is a ANNUAL growing to 1 m (3ft 3in). It is frost tender. It is in leaf from April to October, in flower from July to September, and the seeds ripen. The name Amaranthus dubius was first published by Martius () without diagnosis and description, so it has to be considered invalid. Amaranthus dubius is a weedy plant widespread throughout the humid lowland tropics. It originates from tropical America, where it is common in the Caribbean.
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Email this to a friend Print Share on facebook Tweet this. Showing 0 of 0 comments. Amaranthus dubius 1, flowering and fruiting branch; 2, fruit; 3, seed.
Redrawn and adapted by Iskak Syamsudin.
Amaranthus dubius red-leafed variety. Amaranthus dubius early flowering due to dry conditions. Amaranthus dubius perennial variety from Uganda and western Kenya.
Amaranthus dubius Amaranthus dubius Thell. Amaranthus dubius Amaranth Amaranthus dubius Amaranthus dubius Amaranthus dubius! Amaranthus dubius Amaranthus dubius Mart. Amaranthus dubius Amaranthus dubius, Honduras Amaranthus dubius Amaranthus dubius – Wikipedia Amaranthus dubius amaranthus dubius and the x – k – jpg www.
Amaranthus dubius Amaranthus dubius, one of the Amaranthus dubius early flowering due to dry Amaranthus dubius red-leafed variety x – 50k database. Amaranthus dubius Aluka – Amaranthus dubius Mart. Amaranthus dubius is a weedy plant widespread throughout the humid lowland tropics. It originates from tropical America, where it is common in the Caribbean region and from southern Mexico to northern South America.
The cultivated type may have been developed from the weedy ancestor in tropical Asia Indonesia, India and is found in several African and Central American countries, where immigrants have introduced it. Amaranthus dubius is a protected weed used as a pot herb in many African countries, and it possibly occurs in all African lowland areas.
The main use of Amaranthus dubius is as a cooked leaf vegetable. The product is dark green and tender but its taste somewhat neutral. In Kenya it is cooked with bitter leaf vegetables such as nightshades Solanum spp.
Jeffrey to make it more palatable. The leaves easily become soft after 5—10 minutes cooking in lightly salted water. It is not common to add potash. Amaranth leaves in general are recommended as a good food with medicinal properties for young children, lactating mothers and for patients with fever, haemorrhage, anaemia, constipation or kidney complaints. In Tanzania the whole plant is used as a medicine against stomachache. In Uganda Amaranthus dubius plants are used for the preparation of potash.
Amaranthus dubius is a subsistence vegetable and a collected pot herb, seldom found in markets, but in Kenya it is grown on a commercial scale and sold in city markets. No statistical data on production are available. Commercial growers prefer the more productive Amaranthus cruentus. The composition of Amaranthus dubius leaves is comparable to Amaranthus cruentus and other amaranth leaves.
The average composition of amaranth leaves per g edible portion is: The leaves and stems contain nitrate, mostly in the stems, and also oxalate at a level comparable to other green leaf vegetables. Most people cook amaranth in ample water and discard the cooking water containing soluble nitrate and oxalate. The presence of a rather high content of hydrocyanic acid and oxalic acid makes amaranth less suitable for fresh consumption by humans and as fodder for animals.
Amaranthus dubius can be substituted by other amaranths or other dark green leaf vegetables. Erect annual herb, up to cm tall; stems slender to stout, branched, glabrous or upwards, especially in the inflorescence, with short to rather long hairs. Leaves arranged spirally, simple, without stipules; petiole up to 8. Inflorescence spikelike or paniculate, axillary and terminal, the terminal one up to 25 cm long, consisting of glomerules more or less isolated at base of inflorescence and agglomerated towards apex; bracts up to 2.
Flowers unisexual, subsessile, with 4— 5 tepals up to 2. Fruit an ovoid-urceolate capsule c. Seed lenticular, compressed, c. Amaranthus comprises about 70 species, of which about 40 are native to the Americas.
It includes at least 17 species with edible leaves. It has been postulated as an allotetraploid, with Amaranthus spinosus L. Also, a DNA analysis of the various genomes could not confirm Amaranthus spinosus and Amaranthus hybridus as ancestors of Amaranthus dubius.
It is almost impossible to make a distinction between Amaranthus dubius and Amaranthus spinosus based on morphological characters; Amaranthus spinosus has axillary spines which are not present in Amaranthus dubius. Other more or less reliable differences are the greater number of terminal male flowers in the inflorescences of Amaranthus spinosus and the smaller pores of the pollen.
Spontaneous hybrids between Amaranthus dubius and Amaranthus blitum L. Weedy Amaranthus dubius is a small prostrate plant found in open places on wasteland. Cultivated types of Amaranthus dubius differ greatly from weedy types; the plants are larger, more erect and more succulent. Several local types and cultivars occur.
Amaranthus dubius Mart. ex Thell.
Emergence of the seedling takes place 3—5 days after sowing. The vegetative development is fast. Like maize and sugar cane, the genus Amaranthus is characterized by the C 4 -cycle photosynthetic pathway, which means a high rate of photosynthesis at high temperature and radiation. Flowering may start 4—8 weeks after sowing.
The plants continue to produce new shoots when older branches are already blooming. Pollination is effected by wind but the abundant pollen production causes a high rate of self-pollination. The first seeds mature about 6 weeks after sowing. In backyards with repeated pickings, Amaranthus dubius plants may become perennial, up to 2 years old. Amaranthus dubius is frequently found in tropical humid lowland from sea level up to m altitude, and also but much less at higher elevations up to m.
It is a common plant in waste places, roadsides, flood plains, river banks and cleared forest areas. It shows a weak quantitative short-day reaction. Shade is disadvantageous except in cases of drought stress.
Amaranths like fertile, well-drained soils with a loose structure. At harvest growers spare a few vigorous plants for seed.
Market seed production in the field smaranthus around kg seed per ha in a five-month period. For commercial seed production an isolation distance of m should be respected.
In the wild and in home gardens the seed of fruiting plants scatters and gives rise to new plants automatically. The seed may remain dormant in the soil for several years. It germinates when it comes to the surface or in the top 3 cm of the soil. Yet in germination trials with vegetable types, germination was stimulated by darkness.
The seed may be mixed with sand for easier sowing. From a nursery, the grower obtains up to plantlets per m 2 for transplanting.
Amaranthus dubius is especially well-suited to repeated cutting. For market production Amaranthus dubius is normally grown as a sole crop on beds. It is also found in intercropping systems with food crops.
In fields and home vubius, the only care given to weedy Amaranthus dubius plants is selective weeding. Amaranthus dubius is fast growing, albeit less than the more commonly cultivated Amaranthus cruentus. Because of the rather strong growth of Amaranthus dubiusweeds in transplanted plots are not very troublesome, except nut grass Cyperus rotundus L.
If rainfall is not sufficient, irrigation by sprinkling should be done before the plants reach their wilting point. Amaranthus dubius is much more susceptible to drought than Amaranthus cruentus. Water shortage causes early flowering, which reduces the yield and the market quality. Amaranth is a very aamaranthus consumer of minerals.
On poor soils only modest crops can be produced.
Amaranth responds to high dubuis of organic fertilizer. A split application is recommended during the rainy season. Nitrate-N is better than ammonium-N. Amaranth does not seem to need to be rotated with other crops since no serious soilborne disease has been observed. In general Amaranthus dubius is susceptible to the main pests and diseases of Amaranthus cruentusbut it is less susceptible to stemrot caused by the fungus Choanephora cucurbitarumthe main disease of Amaranthus cruentusand to damping-off caused by Pythium.
For this reason the former is recommended for cultivation during the rainy season. No virus diseases have been reported. Amaranth is not very susceptible to nematode damage. Insects are a serious problem for amaranth growers. Caterpillars Hymenia recurvalisSpodoptera lituraHeliothis armigera and sometimes grasshoppers are the most harmful pests.