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''Brassicoraphanus'' is the name for all the intergeneric hybrids between the genera ''Brassica'' (cabbages, etc.) and ''Raphanus'' (radish). The name comes from the combination of the genus names. Both diploid hybrids and allopolyploid hybrids are known and share this name. Early experimental crosses between species of these two genera had been sterile or nearly sterile, but large-scale experiments by Soviet agronomist Georgi Dmitrievich Karpechenko using ''Raphanus sativus'' and ''Brassica oleracea'' were remarkable because some of the plants produced hundreds of seeds. The second generation were allopolyploids, the result of gametes with doubled chromosome numbers.〔Karpechenko, G.D. 1927, Polyploid hybrids of ''Raphanus sativus'' X ''Brassica oleracea'' L. ''Bulletin of Applied Botany'' 17: 305-408.〕〔Karpechenko, G.D. 1928/1989. Polyploid hybrids of ''Raphanus sativus'' L. X ''Brassica oleracea'' L. In ''Classic papers in horticultural science''. Edited by J. Janick. The Blackburn Press pp. 442–525.〕〔Karpechenko, G.D. 1918. Polyploid hybrids of ''Raphanus sativus'' L. X ''Brassica oleracea'' L. ''Zeitschrift für induktive Abstammungs- und Vererbungslehre'' 48 :1–85.〕 As Karpechenko realized, this process had created a new species, and it could justifiably be called a new genus, and proposed the name ''Raphanobrassica'' for them, but the earlier name ''Brassicoraphanus'' has priority. Plants of this parentage are now known as radicole.〔(L.W. Shemilt, Chemistry and world food supplies: the new frontiers, p 573 )〕 Two other fertile forms of ''Brassicoraphanus'' are known by the following informal names: * The Raparadish group are allopolyploid hybrids between ''Raphanus sativus'' and ''Brassica rapa'', used as fodder crops * Raphanofortii is the allopolyploid hybrid between ''Brassica tournefortii'' and ''Raphanus caudatus''〔Choudhary, B.R., Joshi, P., and Singh, K. 2000. Synthesis, morphology and cytogenetics of Raphanofortii (TTRR, 2n = 38): a new amphidiploid of hybrid ''Brassica tournefortii'' (TT, 2n = 20) × ''Raphanus caudatus'' (RR, 2n=18). TAG Theoretical and Applied Genetics 101(5): 990-999. 10.1007/s001220051572.〕 Currently, it is thought that a great part of the flowering plants have some hybridization and polyploidization among their ancestors.〔Otto, S.P., and Whitton, J. 2000. Polyploidy: incidence and evolution. ''Annual Review of Genetics'' 34: 401–437.〕 ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Brassicoraphanus」の詳細全文を読む スポンサード リンク
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