Carl Linnaeus described three species within the genus: the cultivated radish (Raphanus sativus), the wild radish or jointed charlock (Raphanus raphanistrum), and the rat-tail radish (Raphanus caudatus). Various other species have been proposed (particularly related to the East Asian daikon varieties) and the rat-tail radish is sometimes considered a variety of R. sativus, but no clear consensus has emerged.
Raphanus species grow as annual or biennial plants, with a taproot which is much enlarged in the cultivated radish. Unlike many other genera in the family Brassicaceae, Raphanus has indehiscent fruit that do not split open at maturity to reveal the seeds. The genus is native to Asia, but its members can now be found worldwide. Growing wild, they are regarded as invasive species in many regions.
- "Raphanus confusus". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA). Retrieved 4 January 2018.
- Raphanus confusus Tropicos.org Missouri Botanical Garden. 01 Dec 2011
- Oxford English Dictionary, 3rd ed. "Raphanus, n." Oxford University Press (Oxford), 2008.
- Moghe, Gaurav (May 2014). "Consequences of Whole-Genome Triplication as Revealed by Comparative Genomic Analyses of the Wild Radish Raphanus raphanistrum and Three Other Brassicaceae Species". The Plant Cell. 26 (5): 1925–1937. doi:10.1105/tpc.114.124297. PMC 4079359. PMID 24876251.