This is a list of rice cultivars, also known as rice varieties. There are several species of grain called rice. Asian rice (Oryza sativa) is most widely known and most widely grown, with two major subspecies (indica and japonica) and over 40,000 varieties. Also included in this list are varieties of African rice (Oryza glaberrima) and wild rice (genus Zizania).
Rice may vary in genetics, grain length, color, thickness, stickiness, aroma, growing method, and other characteristics, leading to a vast number of cultivars. For instance, over nine major cultivars of rice exist for the purpose of making sake alone. The two subspecies of Asian rice, indica and japonica, can generally be distinguished by length and stickiness. Indica rice is long-grained and unsticky, while japonica is short-grained and glutinous.
Rice can also be divided on the basis of processing type into the two broad categories of brown and white. Brown rice is whole grain, with only the inedible hull of the seed removed, while white rice additionally has the bran and germ removed through the process of milling. Milled rice may not necessarily actually be white in color; there are purple, black, and red variants of rice, which can be eaten whole grain or milled.
The cultivars listed in this article may vary in any number of these characteristics, and most can be eaten whole grain or milled (brown or white), although there are often strong cultural preferences for one or the other, depending on variety and region.
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