Scientists have identified the carrot genes responsible for traits such as those that give the vegetable abundant vitamin A.
Researchers sequenced the genome of the carrot, an increasingly important root crop worldwide. The genome may point to ways to improve carrots through breeding, including increasing their nutrients and making them more productive and more resistant to disease, pest and drought, the researchers said.
“Carrots are an interesting crop to work on because of their wide range of diversity. They are familiar to everyone, and generally well-regarded by consumers, but like most familiar things, people don’t necessarily know the background stories,” said University of Wisconsin horticulture professor and geneticist Phil Simon.
Worldwide carrot consumption quadrupled between 1976 and 2013 and they now rank in the top 10 vegetable crops globally, the researchers said. In the past four decades, carrots have been bred to be more orange and more nutritious, with 50 per cent more nutrients.
The vitamin A in carrots arises from their orange pigments, known as carotenoids. The study identified genes responsible for carotenoids as well as pest and disease resistance and other characteristics. Vitamin A also is important not only for eyesight but for immune function, cellular communication, healthy skin and other purposes.
The earliest record of carrots as a root crop dates from 1100 years ago in Afghanistan, but those were yellow carrots and purple ones, not orange ones. Paintings from 16th century Spain and Germany provide the first unmistakable evidence for orange carrots.
The wild ancestors of carrots were white, the researchers said. While orange carrots are most commonly grown, some purple and yellow carrots are grown from the Middle East to South Asia, while some red carrots are grown in Asia.
