Brassica (pronounced /ˈbræsɨkə/ brás-si-ca) is a genus of plants in the mustard family (Brassicaceae). The members of the genus may be collectively known either as cabbages, or as mustards. Crops from this genus are sometimes called cole crops, which is derived from the Latin caulis, meaning stem or cabbage.
This genus is remarkable for containing more important agricultural and horticultural crops than any other genus. It also includes a number of weeds, both wild taxa and escapees from cultivation. It includes over 30 wild species and hybrids, and numerous additional cultivars and hybrids of cultivated origin. Most are annuals or biennials, but some are small shrubs. Due to their agricultural importance, Brassica plants have been the subject of much scientific interest. Six particularly important species (Brassica carinata, B. juncea, B. oleracea, B. napus, B. nigra and B. rapa) are derived by combining the chromosomes from three earlier species, as described by the Triangle of U theory.
The genus is native in the wild in western Europe, the Mediterranean and temperate regions of Asia. In addition to the cultivated species, which are grown worldwide, many of the wild species grow as weeds, especially in North America, South America, and Australia. Contents
Almost all parts of some species or other have been developed for food, including the root (rutabaga, turnips), stems (kohlrabi), leaves (cabbage, brussels sprouts), flowers (cauliflower, broccoli), and seeds (many, including mustard seed, and oil-producing rapeseed). Some forms with white or purple foliage or flowerheads are also sometimes grown for ornament.
Brassica species are sometimes used as food plants by the larvae of a number of Lepidoptera species—see List of Lepidoptera that feed on Brassica.
Brassica vegetables are highly regarded for their nutritional value. They provide high amounts of vitamin C and soluble fiber and contain multiple nutrients with potent anti-cancer properties: 3,3'-Diindolylmethane, sulforaphane and selenium. Boiling reduces the level of anti-cancer compounds, however, steaming, microwaving, and stir frying does not result in significant loss. Steaming the vegetable for 3-4 minutes is recommended to maximize sulforaphane.
Brassica vegetables are rich in indole-3-carbinol, a chemical which boosts DNA repair in cells and appears to block the growth of cancer cells. Brassicas are also a good source of carotenoids, with broccoli having especially high levels. Researchers at the University of California at Berkeley have recently discovered that 3,3'-Diindolylmethane in Brassica vegetables is a potent modulator of the innate immune response system with potent anti-viral, anti-bacterial and anti-cancer activity; however, it also is an antiandrogen. Brassica vegetables also contain goitrogens, which are foods that suppress thyroid function. This can induce hypothyroidism and goiter.
There is some disagreement among botanists on the classification and status of Brassica species and subspecies. The following is an abbreviated list, with an emphasis on economically important species.
B. carinata: Abyssinian Mustard or Abyssinian Cabbage, used to produce biodiesel.
B. elongata: Elongated Mustard
B. fruticulosa: Mediterranean Cabbage
B. juncea: Indian Mustard, Brown and leaf mustards, Sarepta Mustard
B. napus: Rapeseed, Canola, Rutabaga (Swede Turnip)
B. narinosa: Broadbeaked Mustard
B. nigra: Black Mustard
B. oleracea: Kale, Cabbage, Broccoli, Cauliflower, Kai-lan, Brussels sprouts, Kohlrabi
B. perviridis: Tender Green, Mustard Spinach
B. rapa (syn B. campestris): Chinese cabbage, Turnip, Rapini, Komatsuna
B. rupestris: Brown Mustard
B. septiceps: Seventop Turnip
B. tournefortii: Asian Mustard
Deprecated species names
B. kaber (Wild Mustard or Charlock)—see Sinapis arvensis
B. alba or B. hirta (White or Yellow mustard)—see Sinapis alba
B. geniculata (Hoary mustard)—see Hirschfeldia incana
Genome sequencing and genetics
Bayer Cropscience (in collaboration with BGI-Shenzhen, China, Keygene N.V., the Netherlands and the University of Queensland, Australia) announced it had sequenced the entire genome of rapeseed/canola (Brassica napus) and its constituent genomes present in Brassica rapa and Brassica oleracea in 2009. The B. rapa genome is currently being sequenced by the Multinational Brassica Genome Project. This also represents the A genome component of the amphidiploid crop species B. napus and B. juncea.