''Brassica rapa'' is a

plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they are predominantly Photosynthesis, photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with c ...

species that has been widely cultivated into many forms, including the turnip (a root vegetable), komatsuna, napa cabbage, bomdong, bok choy, and

rapini Rapini (broccoli rabe or raab) () is a green cruciferous vegetables, cruciferous vegetable, with the leaves, buds, and stems all being edible; the buds somewhat resemble broccoli. Rapini is known for its bitter taste, and is particularly associ ...

. ''Brassica rapa'' subsp. ''oleifera'' is an oilseed commonly known as turnip rape, field mustard, bird's rape, and keblock. Rapeseed oil is a general term for oil from some ''Brassica'' species. Food grade oil made from the seed of low- erucic acid Canadian-developed strains is also called canola oil, while non-food oil is called colza oil. Canola oil can be sourced from ''Brassica rapa'' and ''

Brassica napus Rapeseed (''Brassica napus'' subsp. ''napus''), also known as rape and oilseed rape and canola, is a bright-yellow flowering member of the family Brassicaceae (mustard or cabbage family), cultivated mainly for its oil-rich seed, which naturall ...

'', which are commonly grown in Canada, and '' Brassica juncea'', which is less common.

History

The geographic and genetic origins of ''B. rapa'' have been difficult to identify due to its long history of human cultivation. It is found in most parts of the world, and has returned to the wild many times as a feral plant or

weed A weed is a plant considered undesirable in a particular situation, growing where it conflicts with human preferences, needs, or goals.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. Pla ...

. Genetic sequencing and environmental modelling have indicated that ancestral ''B. rapa'' likely originated 4000 to 6000 years ago in the Hindu Kush area of Central Asia, and had three sets of chromosomes, providing the genetic potential for a diversity of form, flavour, and growth. Domestication has produced modern vegetables and oil-seed crops, all with two sets of chromosomes. Oilseed

subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...

(subsp. ''oleifera'') of ''Brassica rapa'' may have been domesticated several times from the

Mediterranean The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

, starting as early as 2000 BC. There are descriptions of ''B. rapa'' vegetables in Indian and Chinese documents from around 1000 BC. Edible turnips were possibly first cultivated in northern Europe, and were an important food in

ancient Rome In modern historiography, ancient Rome is the Roman people, Roman civilisation from the founding of Rome, founding of the Italian city of Rome in the 8th century BC to the Fall of the Western Roman Empire, collapse of the Western Roman Em ...

. The turnip then spread east to China, and reached Japan by 700 AD. In the 18th century, the turnip and the oilseed-producing variants were thought to be different species by

Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

, who named them ''B. rapa'' and ''B. campestris''. Twentieth-century taxonomists found that the plants were cross fertile and thus belonged to the same species. Since the turnip had been named first by Linnaeus, the name ''Brassica rapa'' was adopted.

Uses

Many butterflies, including the small white, feed from and pollinate the ''B. rapa'' flowers. The young leaves are a common leaf vegetable and can be eaten raw; older leaves are typically cooked. The taproot and seeds can also be eaten raw, although the seeds contain an oil that can cause irritation for some people.

Cultivars

References

External links

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PROTA (Plant Resources of Tropical Africa) database record on ''Brassica rapa'' L.
{{Taxonbar, from=Q3384 rapa Leaf vegetables Plants described in 1753 Taxa named by Carl Linnaeus Root vegetables Space-flown life