Raphanobrassica

taxobox
name = Raphanobrassica
regnum = Plantae
unranked_divisio = Angiosperms
unranked_classis = Eudicots
unranked_ordo = Rosids
ordo = Brassicales
familia = Brassicaceae
genus = "Raphanobrassica"|

"Raphanobrassica" includes all intergeneric hybrids between the genera "Raphanus" (radish) and "Brassica" (cabbages, etc). The name comes from the combination of the genus names for radish and cabbage. Some botanists prefer to use the name "Brassicoraphanus", particularly for plants derived from a cross where "Brassica" was the maternal parent (but neither name has been validly published).

The first "Raphanobrassica" or "rabbage", an allopolyploid cross between the radish ("Raphanus sativus") and cabbage ("Brassica oleracea"), was obtained by the Soviet agronomist Georgi Dmitrievich Karpechenko, in 1928.

Plants of this parentage are now known as radicole. Two other fertile forms of "Raphanobrassica" are known. Raparadish, an allopolyploid hybrid between "Raphanus sativus" and "Brassica rapa" is grown as a fodder crop. "Raphanofortii" is the allopolyploid hybrid between "Brassica tournefortii" and "Raphanus caudatus".

For gastronomists, (those interested in food) this plant may have seemed a disappointment, since all the resulting hybrids of this crossing have radish leaves and cabbage roots -- the two non-edible parts of its ancestors. For biologists, however, the "Raphanobrassica" is an extremely interesting plant, because - in spite of its hybrid nature - it is not sterile. This led some botanists to propose that the accidental hybridization of a flower by pollen of another species in nature could be a mechanism of speciation common in higher plants. Currently, it is thought that a great part of the flowering plants have some hybridization among their ancestors, particularly in the case of the orchids.

References

Karpechenko, G.D., Polyploid hybrids of "Raphanus sativus" X "Brassica oleracea" L., Bull. Appl. Bot. 17:305-408 (1927).

Terasawa, Y. Crossing between "Brassico-raphanus" and "B. chinensis" and "Raphanus sativus". Japanese Journal of Genetics. 8(4): 229–230 (1933).

External links

* [http://www.holysmoke.org/cretins/speci.htm Observed Instances of Speciation]