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Amaranthus L. spp.

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Family :

Famille :

Amaranthaceae

Synonym(s) :

Synonyme(s) :

Common Name(s) :

Nom(s) commun(s) :

Amaranth

(FNA 2024)
Pigweed (FNA 2024; USDA 2024)

Tumble pigweed (Amaranthus albus) seeds and capsule

  • Tumble pigweed (Amaranthus albus) seeds and capsule

  • Tumble pigweed (Amaranthus albus) seed

  • Tumble pigweed (Amaranthus albus) seed; hilum view

  • Prostrate pigweed (Amaranthus blitoides) seeds and capsule

  • Prostrate pigweed (Amaranthus blitoides) seeds

  • Prostrate pigweed (Amaranthus blitoides) seed

  • Amaranthus blitum subsp. blitum seed

  • Amaranthus blitum subsp. blitum seeds

  • Smooth pigweed (Amaranthus hybridus) seed

  • Smooth pigweed (Amaranthus hybridus) seeds and capsule

  • Smooth pigweed (Amaranthus hybridus) seeds

  • Amaranthus muricatus seeds and capsule

  • Amaranthus muricatus seed

  • Palmer’s pigweed (Amaranthus palmeri) seeds and capsule

  • Palmer’s pigweed (Amaranthus palmeri) seed

  • Amaranthus palmeri open capsule and seed

  • Green pigweed (Amaranthus powellii) seeds

  • Green pigweed (Amaranthus powellii) seed

  • Red-root pigweed (Amaranthus retroflexus) seeds

  • Red-root pigweed (Amaranthus retroflexus) seeds and capsule

  • Red-root pigweed (Amaranthus retroflexus) seed

  • Red-root pigweed (Amaranthus retroflexus) seeds

  • Red-root pigweed (Amaranthus retroflexus) seed

  • Amaranthus spinosus seeds and capsule

  • Amaranthus spinosus seed

  • Amaranthus spinosus seed, hilum view

  • Tall water-hemp (Amaranthus tuberculatus); seeds

  • Tall water-hemp (Amaranthus tuberculatus); seeds and capsule

  • Tall water-hemp (Amaranthus tuberculatus); seed

  • Tall water-hemp (Amaranthus tuberculatus) seed; hilum view

  • Amaranthus viridis seeds and capsule

  • Amaranthus viridis seed

Explore More :

Explore plus :

Overview

Aperçu

Regulation :

Remarques Réglementation:

    Regulation Notes:

    Distribution :

    Répartition :

    The Amaranthus genus consists of about 70 native and introduced species on every continent except Antarctica, but mostly tropical, subtropical, and warm-temperate zones, with some found in temperate zones and others with nearly global distribution (FNA 1993+). Some species have long been cultivated as cereal crops in the Americas and as potherbs in Asia, resulting in natural selection for success in disturbed human habitats (Sauer 1967).

    Amaranthus is widespread in North America, with about 30 native and another 13 introduced in the USA (USDA 2024), excluding Hawaii and the Pacific Basin. There are 20 species present in Canada, including 2 native, 10 introduced, 7 hybrids, and 1 ephemeral species found throughout most of Canada except for YT, NT, and Labrador (Brouillet et al. 2010+).

    Habitat and Crop Association :

    Habitat et Cultures Associées :

    Amaranthus species can grow in low-nutrient soils and tolerate wide temperatures and variations in light levels with a high tolerance to drought (Liu and Stützel 2004), heat, salt, and stress (Riggins et al. 2021). They can be found from sea level to 4000 m or more (Netshimbupfe et al. 2023).

    A. retroflexus L. and A. viridis L. are among the most widely distributed Amaranthus species, with A. retroflexus a serious weed of Beta vulgaris L. subsp. vulgaris (sugar beet), Gossypium hirsutum L. (cotton), Helianthus annuus L. (sunflower), Hordeum vulgare L. subsp. vulgare (barley), Triticum aestivum L. subsp. aestivum (wheat), Zea mays L. subsp. mays (corn or maize) and vegetable crops (Holm et al. 1997). A. virdis is a serious weed in similar crops but also in tropical species including Carica papaya L. (papaya), Musa L. spp. (banana) and Mangifera indica L. (mango) (Holm et al. 1997).

    Amaranthus species exhibit preferences for climate and crop type, and have an uneven global distribution. A. retroflexus is common in grain and vegetable crops in cooler regions of the northern hemisphere in North America, Europe and the former Soviet Union (Holm et al. 1997). In North America, A. hybridus L. grows best in milder and more humid areas in the east than A. powellii L., which evolved in dry, mountainous habitats in the west (Sauer 1967; Weaver and McMillan 1980). A. viridis, A. dubius L. and A. spinosus L. prefer warm and humid areas in Asia, India and Africa (Sauer 1967; Holm et al. 1997). A. quitensis Kunth is an important weed in South America, and A. blitum L. in Europe and Asia (Assad et al. 2017; Bayón 2022).

    Amaranthus palmeri S. Watson, in particular, has spread worldwide through human-assisted seed dispersal and agricultural expansion (Ward et al. 2013) and is considered one of the most widespread and severe agronomic weeds in the United States and worldwide due in part to its herbicide resistance (Kistner and Hatfield 2018), as well as its robust growth, ability to compete with crops for water, light, and nutrients, high genetic diversity, and pollen that can travel long distances, resulting in multiple forms of resistance that threaten the economic viability of major crops (Mahoney et al. 2021). It and other resistant species are major herbicide-resistant pests of Zea mays L. subsp. mays (corn), Glycine max (L.) Merr. (soybean), and Gossypium hirsutum L. (cotton) (Heap 2024).

    Economic Use, cultivation area, and Weed Association :

    Utilisation économique, zone de culture et association de mauvaises herbes :

    Amaranthus as a vegetable (mostly A. tricolor L.) and grain (mostly A. cruentus L., A. hypocondriacus L., and A. caudatus L.) are cultivated globally, with China, Russia, Bolivia, Ecuador, and Peru being the top producers (Bvenura and Kambizi 2022). Although, there has been significant recent interest in Africa (Gelaye 2023) and Mexico (Hoidal et al. 2019) as a nutritional food-source and cash crop for small-scale farmers.

    In the Americas, Amaranthus has been domesticated three separate times from South to Central America and has been widely used as a human food source for thousands of years (Sauer 1967). In North America, multiple species have been used by numerous indigenous peoples across the United States for food, dye, and ceremonial purposes (NAEB 2019).

    Amaranthus species are high-yielding plants producing 700 to 1,000 kg of grain per hectare and 4000 kg of leaves when grown in fertile soils (Netshimbupfe et al. 2023). While there is renewed interest in growing Amaranthus as a dual vegetable and grain crop, it has been largely unutilized (Achigan-Daiko 2014; Hoidal et al. 2019; Riggins et al. 2021). Depending on the environmental conditions, defoliation for vegetable use does not affect grain production, even at 50% defoliation rates or more (Hoidal et al. 2019).

    Amaranthus shows great promise as a valuable nutritional food source rich in protein, minerals, and Vitamins A and C that still grows well under current conditions of high carbon dioxide, heat (Blair and Riggins 2023), and water stress (Vargas-Ortiz et al. 2021), while other crops show significant declines in similar conditions. It could be particularly valuable in low-income regions due to its extreme adaptability to thrive in poor conditions, having no major diseases, and high genetic diversity and phenotypic plasticity (Rastogi and Shukla 2013), showing great future crop potential.

    A. hybridus and A. powellii are common weeds of the cultivated grain Amaranthus crops (Sauer 1967).

    Duration of Life Cycle :

    Durée du cycle vital:

    Annual, rarely perennial

    Dispersal Unit Type :

    Type d’unité de dispersion :

    Utricle, seed

    General Information

    RENSEIGNEMENTS GÉNÉRAUX

    The Amaranthus genus is believed to have originated in Central America, with the ancestor(s) of the Eurasian/African native Amaranthus species dispersed from South America before European contact (Assad et al. 2017; Waselkov et al. 2018).

    Amaranthus is known to form interspecific hybrids, especially among cultivated grain-amaranths, although the degree of hybridization is often overestimated and instead are often infraspecific forms of morphologically variable species (FNA 1993+). Most commonly, hybridization occurs among A. retroflexus, A. hybridus, and A. powellii, as well as the domesticated species A. hypochondriacus, A. cruentus, and A. caudatus (Costea et al. 2001).

    Amaranthus species in the subgenus Acnida have female and male flowers on separate plants (dioecious) and are native to North America, including the weed species A. palmeri and A. tuberculatus (Moq.) J. D. Sauer (Steckel 2007). Evidence has been found that plants of A. palmeri are able to set seed without fertilization (Trucco et al. 2007).

    Some studies suggest that the genus shows significant medicinal potential (Baraniak and Kania-Dobrowolska 2022).

    The natural adaptive ability of Amaranthus species resulted in A. retroflexus, A. hybridus and A. powellii being the first species to demonstrate resistance to triazines in the 1970s (Holm et al. 1997). Since then, resistant biotypes of several species to glyphosate, triazine or acetolactate synthase-inhibiting herbicides have been reported (Assad et al. 2017). A. hybridus, A. palmeri, A. retroflexus, A. powellii, A. spinosus, and A. tuberculatus have become herbicide-resistant agricultural pests worldwide.

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    Identification

    Identification

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    • Utricle

      Size

      • Amaranthus species utricle size ranges from literature:
        • Length: 1.2-3.0 mm (FNA 1993+)
        • Length: 1.2–3.5 mm; width: 0.9-3.5 mm (Iamonico 2015)
      • Amaranthus albus utricle size (smallest utricle):
        • Diameter: 1.5 mm (FNA 1993+)
        • Length: (1.2–)1.4–1.8 mm; width: 1.0–1.2(–1.4) mm (Iamonico 2015)
      • Amaranthus blitum utricle size (largest utricle):
        • Diameter: 1.2–2.5(–3) mm (FNA 1993+)
        • Length: 1.9-3.5 mm (Iamonico 2015)
      • Amaranthus retroflexus utricle size (common weed) :
        • Length : 1.5-2.5 mm (FNA 1993+)
        • Length : 1.5–2.5 mm; width: 1.0–1.3 mm (Iamonico 2015)
      • Amaranthus viridis utricle size (common weed):

      • Length : 1.0-1.6 mm (FNA 1993+)
      • Length : (1.2–)1.4–1.7(–1.9) mm; width: 1.4–1.6(–1.8) mm (Iamonico 2015)

      Shape

      • Utricles are generally oval -shaped, but can be globose, egg-shaped or elongated egg-shaped
      • Utricles can be compressed or inflated in 3D

      Surface Texture

      • Utricles are generally smooth, weakly or strongly wrinkled
      • Some species utricles are wrinkled on the style end, and smooth on the other end (e.g. A. polygonoides L., A. spinosus L.)
      • The utricle of A. spinosus is much larger than the seed, and is spongy or inflated at one end (FNA 1993+)

      Colour

      • Utricles are generally yellowish-brown, light brown or brown
      • A. blitum can have reddish-brown utricles (Iamonico 2015)

      Other Features

      • Utricles may be indehiscent, or dehiscent along a transverse line in the middle of the utricle (circumscissile)
      • Utricles are loosely enclosed generally by 3-5 tepals, the size relative to the utricle and their shape have diagnostic value (FNA 1993+)

      Tumble pigweed (Amaranthus albus) seeds and capsule

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    >

    • Seed

      Size

      • Amaranthus retroflexus seed length*: 0.73-1.2 mm; width: 0.66-1.1 mm
      • Amaranthus tuberculatus seed length*: 0.81-1.0 mm; width: 0.65-0.88 mm
      *Note: minimum and maximum based on 10 seeds in normal range of this species using image measurement protocol (ISMA 2020).
      • Amaranthus species seed size ranges from literature:
        • Seed length: 0.8-1.6 mm; width: 0.7-1.5 mm (Bojňanský and Fargašová 2007)
        • Seed diameter: 0.6-1.6 mm (FNA 1993+)
      • Amaranthus albus seed size (smallest seed):
        • Seed length: 0.7-1.0 mm; width: 0.6-0.8 mm (Bojňanský and Fargašová 2007)
        • Seed diameter: 0.6-1.0 mm (FNA 1993+)
      • Amaranthus blitoides seed size (largest seed):
        • Seed length: 1.4-1.6 mm; width: 1.3-1.5 mm (Bojňanský and Fargašová 2007)
        • Seed diameter: 1.3-1.6 mm (FNA 1993+)
      • Amaranthus retroflexus seed size (common weed):
        • Seed length: 0.9-1.1 mm; width: 0.8-0.9 mm (Bojňanský and Fargašová 2007)
        • Seed diameter: 1.0–1.2(–1.4) mm (Iamonico 2015)
      • Amaranthus viridis seed size (common weed):
        • Seed diameter: 0.8-1.2 mm (Iamonico 2015)

      Shape

      • Seeds of weedy species are generally egg-shaped or oval-shaped, some species have round seeds
      • Seeds are generally lens-shaped (biconvex) in 3D, some species may be more inflated (e.g. A. albus)
      • A rim or margin is around the outside if the seed, generally more compressed than the center

      Surface Texture

      • Seeds are generally smooth, thin reticulation lines seen under 20 x magnification
      • Reticulation may be ridged or grooved seen under 20x magnification
      • Seeds of some species are stippled (e.g. A. muricatus (Gillies ex Moq.) Hieron., A. viridis, A. blitoides S. Watson)
      • Seed rims generally have grooved reticulation with rectangular interspaces, but can be roughened and look ‘frosted’ (e.g. A. albus)

      Colour

      • Generally shiny or glossy black, reddish-black, dark red, dark brownish with silvery reticulation, may be dull black (e.g. A. blitoides)
      • Some cultivated species are dull yellowish coloured (e.g. A. caudatus, A. hypochondriacus)
      • Varieties of A. caudatus may be dull pinkish coloured
      • Immature seeds are red or orange

      Other Features

      • The hilum is a small notch along the edge of the seed; near the narrow end if the seed is oval or egg-shaped
      • The hilum may be open in a V-shape or closed in certain species and have diagnostic value (e.g. A. palmeri generally has a V-shaped hilum; hilum variable in A. retroflexus)
      • The hilum has 2 outgrowths to either side (hilum lobes) and the length or protrusion has diagnostic value in certain species (e.g. A. tuberculatus generally has long hilum lobes, A. palmeri has short ones)

      Tumble pigweed (Amaranthus albus) seeds and capsule

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    >

    • Embryo

      Size

      • Embryo partially fills the seed

      Shape

      • Embryo curved or circular

      Endosperm

      • Endosperm (technically perisperm) is hard and translucent whitish, or white in cultivated species.

      Other Features

      • Embryo peripheral position
      • Embryo is white-coloured

    Identification Tips

    CONSEILS POUR L’IDENTIFICATION

    Seeds and fruits of Amaranthus species have several distinguishing features:

    • Small seed size, less than 1.6 mm long
    • Generally oval or egg-shaped, same species have round seeds
    • Lens-shaped (biconvex) in 3D, compressed or inflated
    • Dark-coloured, generally glossy blackish or dark red
    • Surface generally smooth, faint ridged or grooved reticulation seen under 20x magnification. Some seeds have a stippled surface
    • Edge of seeds generally marked with slight grooved reticulation, appears ‘frosted’ under 10x magnification
    • Hilum visible as an open, V-shaped notch or closed slit along narrow edge of seed, with lobes to either side
    • Embryo peripheral position, curved or circular
    • Endosperm generally translucent whitish coloured
    • Fruit a utricle, loose around the seed, indehiscent or opens by a transverse line (circumscissile)

    Tumble pigweed (Amaranthus albus) seed

    Additional Botany Information

    AUTRES RENSEIGNEMENTS BOTANIQUES

    Flowers/Inflorescence

    • Inflorescences are terminal and/or axillary, arranged in spikes, branched inflorescences (thyrses, panicles), or appearing as congested globose heads (glomerules). When terminal, inflorescences are often subtended by reduced leaves; each inflorescence unit (dichasium) is subtended by persistent bracts (FNA 1993+).
    • Bracts are egg-shaped, lanceolate, linear, triangular, or narrowing to a fine point or sometimes proximal bracts are modified into spines (FNA 1993+)
    • Bracts of female flowers are usually not keeled; bracteoles are absent or 1-2 (FNA 1993+). 
    • Unisexual flowers, usually sessile (WFO 2024).
    • Female flowers have 0 or (1-)3-5 usually distinct tepals; tepals are equal or outer ones larger than inner ones and are usually membranaceous, sometimes thin and dry (scarious); stamens are absent or rudimentary; there is 1 pistil and 1 ovule; styles are short (0.1–1 mm) or absent; there are 2-3(-5) slender stigmas (FNA 1993+). 
    • Male flowers have 3-5 equal or subequal tepals; stamens 3-5 (FNA 1993+) or rarely 1 (WFO 2024) with distinct filaments and 4-locular anthers, sterile stamens (pseudostaminodes) are absent, and pistils are absent or rudimentary (FNA 1993+; WFO 2024).
    • Amaranthus can be difficult to identify partly due to extensive, often environmentally-induced morphological variation. In the field examination of monecious female inflorescences to determine the presence or absence of any male flowers and examination of female plants of dioecious species will aid in identification (FNA 1993+), as will the presence of well-developed fruits and seeds. 

    Vegetative Features

    • Herbs, usually annual, rarely short-lived perennials; monoecious (subg. Amaranthus and Albersia) or dioecious (subg. Acnida) (FNA 1993+).
    • Stems are usually branched and smooth or with pubescent hairs; they are erect, flattened with the tips growing upwards (decumbent), or lying along the ground (prostrate); nodal spines are only present in A. spinosus (FNA 1993+). 
    • Leaves are alternate and usually long-petiolate; blades are diamond-shaped to egg-shaped, wide at the tip and tapering to the base (spatulate), lanceolate, rounded, or linear, and may have the wide end at the base or the tip; leaf bases are rounded to narrowly wedge-shaped; margins are usually entire and flat but sometimes slightly wavy; leaf tips are acute, obtuse, notched, or abruptly sharp-pointed (FNA 1993+).

    Amaranthus palmeri plant with inflorescence; Sinaloa, Mexico.

    Similar Species

    ESPÈCES SEMBLABLES

    Similar species are based on a study of seed morphology of various species, and those with similar dispersal units are identified. The study is limited by physical specimen and literature availability at the time of examination, and possibly impacted by the subjectivity of the authors based on their knowledge and experience. Providing similar species information for seed identification is to make users aware of similarities that could possibly result in misidentification.

    Selected similar species of Amaranthus

    Seeds of Amaranthus species can have similar shapes, hila, colour and surface textures, and along with their small size, makes them generally difficult to distinguish to species level. Examination of seeds under 20x magnification will show more details of the features that may aid in determining the species.

    FNA (1993+) Seed Diameter Common Seed Shape Hilum area FNA (1993+)

    Utricle Length
    Subgenus Acnida
    A. palmeri S. Watson  1-1.2 mm Egg-shaped Hilum open, lobes small 1.5–2 mm
    A. tuberculatus (Moq.) J. D. Sauer  0.7-1 mm Round or comma-shaped Hilum closed, lobes large 1.5–2 mm
    Subgenus Albersia
    A. albus L.  0.6-1 mm Round Hilum open or closed, lobes small 1.5 mm
    A. blitoides S. Watson  1.3-1.6 mm Round or egg-shaped Hilum open or closed, lobes small 1.7-2.5 mm
    A. blitum L.  (0.8–)1–1.8 mm Round or egg-shaped Hilum open or closed, lobes small 1.2–2.5(–3) mm
    A. crispus (Lesp. & Thévenau) A. Braun ex J. M. Coult. & S. Watson  0.7-1 mm Oval or egg-shaped Hilum open or closed, lobes small 1.5-2 mm
    A. muricatus (Moq.) Hieron.  1-1.2 mm Round Hilum open or closed, lobes small 1.7-2 mm
    A. tricolor L.  1 mm Egg-shaped or oval Hilum open, lobes small 2-2.5 mm
    A. viridis L.  1 mm Egg-shaped or round Hilum open, lobes small 1-1.6 mm
    Subgenus Amaranthus
    A. caudatus L.  1–1.2(–1.5) mm Egg-shaped or round Hilum closed, lobes large 1.5–2(–2.5) mm
    A. cruentus L. 1.2-1.6 mm Egg-shaped Hilum closed, lobes large 2-2.5 mm
    A. dubius Mart. ex Thell. 0.8-1 mm Egg-shaped Hilum open or closed, lobes small 1.5-2 mm
    A. hybridus L. 1-1.3 mm Egg-shaped Hilum closed, lobes large 1.5-2.5 mm
    A. hypochondriacus L. 1-1.4 mm Broad egg-shaped or rround Hilum closed, lobes large (1.5–)2–3 mm
    A. powellii S. Watson 1-1.4 mm Egg-shaped Hilum closed, lobes large 2-3 mm
    A. retroflexus L. 1-1.3 mm Egg-shaped Hilum closed, lobes large 1.5-2.5 mm
    A. spinosus L. 0.7-1 mm Egg-shaped or round Hilum open, lobes small 1.5-2.5 mm

     

    Chenopodium L. species

    The seeds of Amaranthus species can appear similar to small-seeded Chenopodium, Blitum, Dysphania and Oxybasis seeds, and deformed, terete C. album L. seeds. The smooth surface, paired hilum lobes, grooved-reticulate radicle at the hilum end and the textured rim around the outside of Amaranthus seed are distinguishing features.

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    Reference(s)

    Référence(s)

    Achigan-Dako, E.G., Sogbohossou, O.E.D. & Maundu, P. 2014. Current knowledge on Amaranthus spp.: research avenues for improved nutritional value and yield in leafy amaranths in sub-Saharan Africa. Euphytica 197, 303–317. https://doi.org/10.1007/s10681-014-1081-9

    Assad, R., Reshi, Z.A., Jan, S. and Rashid, I. 2017. Biology of Amaranths. Botanical Review 83: 382-436.

    Baraniak, J., & Kania-Dobrowolska, M. 2022. The Dual Nature of Amaranth—Functional Food and Potential Medicine. Foods, 11(4). https://doi.org/10.3390/foods11040618

    Bayón, N.D. 2022. Identifying the weedy amaranths (Amaranthus, Amaranthaceae) of South America. Advances in Weed Science 40(Spec2):e0202200013. https://doi.org/10.51694/AdvWeedSci/2022;40:Amaranthus007

    Blair, M. W., & Riggins, C. 2023. Editorial: Amaranthus: Naturally stress-resistant resources for improved agriculture and human health, volume II. Frontiers in Plant Science, 14. https://doi.org/10.3389/fpls.2023.1329377

    Bojňanský, V. and Fargašová, A. 2007. Atlas of Seeds and Fruits of Central and East-European Flora: The Carpathian Mountains Region. Springer, The Netherlands. 1046 pp.

    Brouillet L, Desmet P, Coursol F, Meades SJ, Favreau M, Anions M, Bélisle P, Gendreau C, Shorthouse D, (2010+). Database of Vascular Plants of Canada (VASCAN). Online at http://data.canadensys.net/vascan Accessed February 2, 2024.

    Bvenura C, Kambizi L. Future grain crops. In: Future Foods. Elsevier; 2022:81–105.

    Costea, M., Sanders, A. and Waines, G. 2001. Preliminary results toward a revision of the Amaranthus hybridus species complex (Amaranthaceae). SIDA 19: 931-974.

    Flora of North America (FNA) Editorial Committee, eds. 1993+. Flora of North America North of Mexico [Online]. 22+ vols. New York and Oxford. http://beta.floranorthamerica.org Accessed February 2, 2024.

    Gelaye Y. A Review of Amaranth Crop as a Potential Solution to Ethiopia’s Nutritional Crisis. Nutrition and Dietary Supplements. 2023;15:101-110 https://doi.org/10.2147/NDS.S428058

    Global Biodiversity Information Facility (GBIF) Secretariat. 2024. Amaranthus L. in. GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei via GBIF.org Accessed February 2, 2024.

    Heap, I. The International Herbicide-Resistant Weed Database. Online. Accessed February 3, 2024. Available www.weedscience.org.

    Hoidal, N., Gallardo, M. D., Jacobsen, E., & Alandia, G. 2019. Amaranth as a Dual-Use Crop for Leafy Greens and Seeds: Stable Responses to Leaf Harvest Across Genotypes and Environments. Frontiers in Plant Science, 10. https://doi.org/10.3389/fpls.2019.00817

    Holm, L., Doll, J., Holm, E., Pancho, J. and Herberger, J. 1997. World Weeds, Natural Histories and Distribution. John Wiley & Sons, Inc. New York. 1129 pp.

    Iamonico, D. 2015. Taxonomic revision of the genus Amaranthus (Amaranthaceae) in Italy. Phytotaxa 199: 1–84.

    International Seed Morphology Association (ISMA). 2020. Method for Seed Size Measurement. Version 1.0. ISMA Publication Guide.

    Kietlinski, K.D., Jimenez, F., Jellen, E.N., Maughan, P.J., Smith, S.M. and Pratt, D.B. 2013. Relationships between the weedy Amaranthus hybridus (Amaranthaceae) and the grain amaranths. Crop Science 54:220–228.

    Kistner, E. J., & Hatfield, J. L. 2018. Potential Geographic Distribution of Palmer Amaranth under Current and Future Climates. Agricultural & Environmental Letters, 3(1), 170044. https://doi.org/10.2134/ael2017.12.0044

    Liu, F., & Stützel, H. 2004. Biomass partitioning, specific leaf area, and water use efficiency of vegetable amaranth (Amaranthus spp.) in response to drought stress. Scientia Horticulturae, 102(1), 15-27. https://doi.org/10.1016/j.scienta.2003.11.014

    Mahoney, D. J., Jordan, D. L., Hare, A. T., Leon, R. G., Vann, M. C., Jennings, K. M., Everman, W. J., & Cahoon, C. W. 2021. Palmer Amaranth (Amaranthus palmeri) Growth and Seed Production When in Competition with Peanut and Other Crops in North Carolina. Agronomy, 11(9), 1734. https://doi.org/10.3390/agronomy11091734

    Native American Ethnobotany Database (NAEB). 2019. Native American Ethnobotany Database. Brit.org. http://naeb.brit.org/

    Netshimbupfe, M. H., Berner, J., Van Der Kooy, F., Oladimeji, O., & Gouws, C. 2023. The importance and use of Amaranthus for crop diversification in the SADC region. South African Journal of Botany, 152, 192-202. https://doi.org/10.1016/j.sajb.2022.11.039

    Rastogi, A., & Shukla, S. 2013. Amaranth: a new millennium crop of nutraceutical values. Critical reviews in food science and nutrition, 53(2), 109–125. https://doi.org/10.1080/10408398.2010.517876

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    zeaSauer, J. D. 1967. The Grain Amaranths and Their Relatives: A revised Taxonomic and Geographic Survey. Ann. Missouri Bot. Gard. 54: 103–137.

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    Author(s)

    AUTEUR(S)

    Lyrae Willis, BSc. Environmental Sciences,

    Jennifer Neudorf, Canadian Food Inspection Agency

    contactus@idseed.org

    Last updated
    on 2023-03-27

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