Amaranthus hybridus (Common pigweed, Prince's feather)

Life > eukaryotes > Archaeoplastida > Chloroplastida > Charophyta > Streptophytina > Plantae (land plants) > Tracheophyta (vascular plants) > Euphyllophyta > Lignophyta (woody plants) > Spermatophyta (seed plants) > Angiospermae (flowering plants) > Core Eudicots > Order: Caryophyllales > Family: Amaranthaceae > Subfamily: Amaranthoideae > Amaranthus

Native from eastern USA to South America. Grows as a weed but is also cultivated for the leaves, which are eaten like Spinach. In Setswana and Sesotho languages, the aerial parts of plants that are eaten as green leafy vegetables are referred to as morogo and Amaranthus hybridus is one of these. Amaranthus become poisonous if grown on nutrient rich soils (e.g. on compost heaps and in heavily fertilised soil) because under these conditions they accumulate dangerous levels of oxalates.

Nutritional value

Van der Walt et al. (2009) found that there were high levels of calcium and magnesium in Amaranthus hybridus, higher in fact than the levels recorded from spinach and Swiss chard whereas Iron and Zinc levels were similar to, and selenium levels were lower than, those in the latter two vegetables. Carotenoids levels are reasonably high and similar to those found in spinach. Carotenoids are transformed into vitamin A in the body and hence are nutritionally important. Polyphenols concentrations found in Amaranthus hybridus are similar to those in commercially grown vegetables. The latter substances are important antioxidants and help to prevent thickening of the arteries (atherogenesis).

Hence, Amaranthus hybridus, while being a weed is also a nutritious vegetable, and is especially valuable to resource poor households in rural and peri-urban areas in southern Africa.

Van der Walt et al. (2006) show that toxic Fusarium fungi are more prevalent on Amaranthus hybridus (and other vegetables) that are growing near home-grown maize. There is a problem with maize harbouring high levels of Fusarium that can spread to other crops.

Publications

• van der Walt, A.M., Loots, D.T., Ibrahim, M.I.M. and Bezuidenhout, C.C. 2009. Minerals, trace elements and antioxidant phytochemicals in wild African dark-green leafy vegetables (morogo). South African Journal of Science 105: 444-448.

• van der Walt, A.M., van der Linde, E., Alberts, M., Madjadji, P, Jivan, S.D. and Bezuidenhout, C.C. 2006. Fumonisin-producing Fusarium strains and fumonisins in traditional African vegetables (morogo). South African Journal of Science 102: 151-155.