This winter radish (Raphanus sativus
) belongs to the mustard family, (a.k.a. family Cruciferae or family Brassicaceae - plants with four-petaled flowers) which is a large group that includes mustard
With the size and shape somewhat resembling a plastic 5-liter
coke bottle, it is called 大根("big root") in Japanese
Only the root is eaten most of the time, which is pure white except the top portion that has slightly green skin. It is served raw chopped, raw grated (daikon oroshi, which goes well with cooked fish), cooked, boiled, or pickled (see: Tsukemono (Japanese Pickles)
The earliest records of daikon date back to 2700 B.C. in Egypt
and 1100 B.C. in China, and even appears in kojiki
(the oldest Japanese literature ever found)
by its archaic name "oone", which is the kun-yomi
of the same Kanji
There were many varieties of daikon, until modernization in transportation and agriculture resulted in mass-marketing of only one type of daikon, the aokubi daikon (tr: "green-necked daikon").
Because of its coke bottle shape as mentioned above, it was best for efficient mass transportation. The plant suzushiro of nanakusa
fame is also now a rare type of daikon.
Here are pages with pics of it:
http://www.icon.pref.nagano.jp/usr/kohaku/zatugaku.htm (in Japanese)