The acephala group refers to any type of Brassica which grows without the central 'head' typical of many varieties of cabbage. These are included within the speciesBrassica oleracea, such as kale (Brassica oleracea var. acephala).[1] The name literally means "without a head" in contrast to those varieties known as capitata or "with a head". This group includes a number of species, both wild and cultivated, many of which are grown for their edible leaves and flowers.
Different sources break down the Brassicagenus into different grouping as shown below:
Mabberley
Mabberley (q.v.) has these groups: Napobrassica Group / Pabularia Group / Acephala Group / Alboglabra Group / Botrytis Group / Capitata Group / Gemmifera Group / Gongylodes Group / Italica Group / Tronchuda Group / Chinensis Group / Japonica Group / Pekinensis Group / Perviridis Group / Rapifera Group
Royal Botanic Gardens Kew
Royal Botanic Gardens Kew[2] has eight cultivar groups: Acephala Group (kale, borecole, collards) / Alboglabra Group (Chinese kale, Chinese broccoli, gai lan, kai lan) / Botrytis Group (broccoli, cauliflower, broccoflower, calabrese) / Capitata Group (cabbage, Savoy cabbage, red cabbage) / Gemmifera Group (sprouts, Brussels sprouts) / Gongylodes Group (kohlrabi, knol-kohl) / Italica Group (purple sprouting, sprouting broccoli) / Tronchuda Group (Portuguese cabbage, seakale cabbage)
Acephala means "no head"[12] as the plants have leaves with no central head; the opposite arrangement of white cabbage, or Savoy cabbage. Each cultivar has a different genome owing to mutation,[13] evolution, ecological niche,[14] and intentional plant-breeding by humans. Mabberley (1997, p. 120) has the Acephala group in three sub-groups: kale, borecole, and collards.[15]
References
^Random House Webster's College Dictionary, New York 1992, p. 736 (s.v. kale)
^"RHS Plant Finder". rhs.org.uk. Royal Horticultural Society. Retrieved 25 November 2014.
^(Quote.) "Originally, a general name for any plant of the cabbage kind, genus Brassica (of which the varieties were formerly less distinct than now)." ("colewort, n." OED Online. Oxford University Press, September 2014. Web. 26 November 2014.)
^Mabberley, D. (1997) Mabberley's plant-book : A portable dictionary of plants, their classification and uses. 3rd ed. Cambridge: Cambridge University Press.