Bok Choy

Brassica rapa

"Brassica rapa" is a plant consisting of various widely cultivated subspecies including the turnip; napa cabbage, bomdong, bok choy, and cime di rapa; and "Brassica rapa subsp. oleifera", an oilseed which has many common names, including "turnip rape", "field mustard", "bird rape", and "keblock".
Field mustard introduced - this plant can take on an *amazing* number of forms. It's a common food plant - subspecies you may know (and eat) bok choy, choy sum, Napa cabbage, rapini, tatsoi, turnips and more!! These wild ones escape from gardens and farms and revert to just a pretty yellow weed...  Brassica rapa,Geotagged,Spring,United States

Naming

The oil made from the seed is sometimes also called "canola" or "colza", which is one reason why it is sometimes confused with rapeseed oil, but this comes from a different "Brassica" species. The oilseeds known as canola are sometimes particular varieties of "Brassica rapa" but usually the related species "Brassica napus" and "Brassica juncea".

Researchers at the University of Wisconsin–Madison have selectively bred one subspecies of "B. rapa" to have an extremely short life cycle for use as a model organism in education and experiment. This variety is known by the trademarked name "Wisconsin Fast Plants."
Brassica rapa var. nipposinica, Cultivar: Mizuna As part of the Japanese Mustard greens Mizuna make a great piquant Salad but can also be stir fried or used in soups. Brassica rapa,Geotagged,Germany,Mizuna,Winter

Evolution

In the 18th century the turnip and the oilseed-producing variants were seen as being different species by Carl Linnaeus who named them "B. rapa" and "B. campestris". 20th-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.

Many butterflies, including the small white, pollinate the "B. rapa" flowers.

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Taxonomy
KingdomPlantae
DivisionAngiosperms
ClassEudicots
OrderBrassicales
FamilyBrassicaceae
GenusBrassica
Species