Brassica oleracea (Cabbage, Brussels Sprouts, Broccoli, Kohlrabi, Cauliflower, Kale)

[= Brassica cretica, Brassica insularis, Brassica rupestris]

Life > eukaryotes > Archaeoplastida > Chloroplastida > Charophyta > Streptophytina > Plantae (land plants) > Tracheophyta (vascular plants) > Euphyllophyta > Lignophyta (woody plants) > Spermatophyta (seed plants) > Angiospermae (flowering plants) > Eudicotyledons > Core Eudicots > Rosids > Eurosid II > Order: Brassicales > Family: Brassicaceae > Genus: Brassica

Originates from the Atlantic seaboard of Europe and the Mediterranean. It has been used as a vegetable for more than 2500 years and through selective breeding for particular characteristics of the plant,  six main vegetables have been produced from this one species. 

Wild Brassica oleracea is native to the Atlantic seaboard of Europe (e.g. coastlines of Britain and the Bay of Biscay) and the Mediterranean basin. Six main vegetables have been derived from this wild stock through selection of favourable cultivars by people:

Vegetable	Derived through selection for:
Kale	loose, uncompact leaves (most closely resembles the wild plant).
Cabbage	enlarged terminal buds.
Brussels sprouts	numerous lateral buds.
Kohlrabi	enlarged stems.
Cauliflower	more extensive flowering structures. The whiteness is caused by the outer leaves blocking sunlight and preventing the formation of chlorophyl.
Broccoli	enlarged stems and flowering structures.

It is thought that one of the reasons it has been possible for people to produce so many vegetables from this one species is because it is geographically diverse so that there is a great genetic diversity from which one can draw favourable attributes through selective breeding.

Use of Brassica oleracea can be traced back to Greek and Roman times, at least 2500 years ago. The Greeks were using non-heading Kale-like varieties. The Romans in addition were using a loose-headed cabbage as well as a possible precursor to broccoli. However, it is only from about 1600 onwards that the main varieties (except Brussels Sprouts) are clearly referred to in writings. Brussels Sprouts only started being eaten by the English in the 19th century although its origins go back earlier in continental Europe. Modern day cultivars of Brassica oleracea have been produced that are more pest resistant and which have solid heads that can withstand mechanical harvesting, shipment and storage.

The various forms of Brassica oleracea are mainly cooked or used in salad. Pickled cabbage, known usually as sauerkraut, is a way of cooking cabbage that was introduced to Europe by the Tartars. The pickling process does not destroy the Vitamin C and pickled cabbage was used by the Dutch and British colonists as a defense against scurvy and was also important to the health of Europeans living through long winters. Captain Cook kept his crews healthy on pickled cabbage. 

Brassicas contain substances called goitrins which can interfere with the body’s uptake of iodine and encourage goiter (enlargement of the thyroid) but this is only a problem in people who have a persistent iodine deficiency.

References

• Sauer, J.D. 1993. Historical geography of crop plants - a select roster. CRC Press, Boca Raton, Florida.

Text by Hamish Robertson