According to the Triangle of U theory, B. oleracea is very closely related to five other species of the genus Brassica.
Bermuda Triangle | Research Triangle Park | Research Triangle | Encyclopedia of Triangle Centers | Sunni Triangle | Pascal's triangle | love triangle | Iron Triangle | Bizarre Love Triangle | Virginia Triangle | Triangle of U | Triangle Fraternity | Triangle Film Corporation | Princeton Triangle Club | Mara Triangle | Love triangle | Ilemi Triangle | Bermuda Triangle (album) | Battle of Triangle Hill | Triangle wave | Triangle Transit | Triangle Island | The Incomplete Triangle | Sierpinski triangle | Platinum Triangle | pink triangle | Pedal triangle | Parliamentary Triangle, Canberra | Parliamentary Triangle | Palliser's Triangle |
An interesting genetic relationship between many species of mustard has been observed, and is described as the Triangle of U.