Origins of mandarin and either
citron or
pomelo. Some mandarins are the original wild species, but most are hybrids.
Domestication Mandarins appear to have been domesticated at least twice, in the north and south
Nanling Mountains, derived from separate wild subspecies. Wild mandarins are still found there, including Daoxian mandarines (sometimes given the species name
Citrus daoxianensis) as well as some members of the group traditionally called 'Mangshan wild mandarins', a generic grouping for the wild mandarin-like fruit of the Mangshan area that includes both true mandarins (
mangshanyeju, the southern subspecies) and the genetically distinct and only distantly-related
Mangshanyegan. The wild mandarins were found free of the introgressed pomelo (
C. maxima) DNA found in domestic mandarins. Still, they did appear to have small amounts (~1.8%) of introgression from the
ichang papeda, which grows wild in the same region. The Nanling Mountains are home to northern and southern genetic clusters of domestic mandarins that have similar levels of sugars in the fruit compared to their wild relatives but appreciably (in some almost 90-fold) lower levels of citric acid. The clusters display different patterns of pomelo introgression, have different deduced historical population histories, and are most closely related to distinct wild mandarins, suggesting two independent domestications in the north and south. All tested domesticated cultivars belong to one of these two genetic clusters, with varieties such as Nanfengmiju, Kishu, and Satsuma from the northern domestication event producing larger, redder fruit, while varieties such as Willowleaf, Dancy, Sunki, Cleopatra, King, and Ponkan belong to the smaller, yellower-fruited southern cluster. In the genomic-based species taxonomy of Ollitrault et al., only pure wild type mandarins would fall under
C. reticulata, while the pomelo admixture found in the majority of mandarins would cause them to be classified as varieties of the hybrid bitter orange,
C. aurantium. Genetic analysis is consistent with continental mandarins representing a single species, varying due to hybridization. They have some pomelo DNA, like all domesticated mandarins. == Production ==