Brassica rapa L. subsp. rapa (Turnip )

Crop Type: Garden Crop

Breeding system: Predominantly allogamous

Brassica crops are used for human nutrition; they include important vegetable crops such as B. oleracea (broccoli, cabbage and cauliflower) and B. rapa (Chinese cabbage, pak choi and turnip) as well as oilseed crops such as B. napus, B. juncea and B. rapa which collectively provide 12% of the world edible vegetable oil production (Labana and Gupta 1993).

Concerning B rapa, the cultivated forms probably arose independently in different places of the world from wild B. rapa (Zhao et al. 2005). B. rapa subsp. rapa was first cultivated for its root. Later on, within the same subspecies, a differentiation took place and other vegetable crop, such as turnip tops or greens, spread. Usually, turnip tops are grown in north-western Spain, Portugal and southern Italy.

The cultivation of B. rapa takes place during the winter season. In many cases the same landrace is cultivated for multiple use, allowing the existence of local varieties with high levels of variability. Landraces orientated to the production of turnips develop enlarged root and usually flower late while landraces grown for turnip greens and tops are characterised by early flowering and numerous flowering stalks (Padilla et al. 2005).

References
  • Labana KS, Gupta ML (1993) Importance and Origin. Springer, Berlin, Heidelberg, pp 1–7
  • Padilla G, Cartea ME, Rodríguez VM, Ordás A (2005) Genetic diversity in a germplasm collection of Brassica rapa subsp rapa L. from northwestern Spain. Euphytica 145:171–180. doi: 10.1007/s10681-005-0895-x
  • Zhao J, Wang X, Deng B, et al (2005) Genetic relationships within Brassica rapa as inferred from AFLP fingerprints. Theor Appl Genet 110:1301–1314. doi: 10.1007/s00122-005-1967-y