The orange root crop known for its high beta-carotene content is the carrot. Its scientific name is Daucus carota subsp. sativus, a domesticated form of the wild carrot.
Carrots belong to the Apiaceae family, which also includes celery, parsley, and parsnips. The plant is biennial, but it is normally harvested during its first year, when its thickened taproot is tender and sweet. Orange carrots get their color mainly from beta-carotene, which the body can convert into vitamin A.
Orange is not the only natural carrot color. Heirloom varieties may be white, yellow, red, purple, or nearly black, depending on their pigments. A popular wartime story claimed that eating carrots gave British pilots exceptional night vision during World War II. The real advantage came largely from radar technology, although carrots can contribute to normal vision when they help prevent vitamin A deficiency.