A version of this story appears in the February 2017 issue of National Geographic magazine. Citrus, in many ways, stands alone. So many cultivated species have come from so few primary ancestors.

Zhongxian county in Chongqing, an ideal citrus cultivation base with a history spanning two millenniums, has transformed into ...

The mandarin orange is apparently the most grown among citrus fruits in India. It occupies over 40 percent of the total area ...