Mandarin orange

Citrus reticulata is from Latin, where reticulata means "netted".[6] The name mandarin orange is a calque of Swedish mandarin apelsin [apelsin from German Apfelsine (Apfel + Sina), meaning Chinese apple], first attested in the 18th century. The form "mandarine" derives from the French name for this fruit. The reason for the epithet "mandarin" is not clear; it may relate to the yellow colour of some robes worn by mandarin dignitaries.[7][8]

Mandarin oranges growing on a tree in Crete.

Citrus reticulata is a moderate-sized tree some 7.6 metres (25 ft) in height.[1][6] The tree trunk and major branches have thorns.[1] The leaves are shiny, green, and rather small.[1] The petioles are short, almost wingless or slightly winged.[1] The flowers are borne singly or in small groups in the leaf-axils.[1] Citrus are usually self-fertile (needing only a bee to move pollen within the same flower) or parthenocarpic (not needing pollination and therefore seedless, such as the satsuma). A mature mandarin tree can yield up to 79 kilograms (175 lb) of fruit.[9]

Mandarin oranges in a mesh bag

Mandarin orange seeds

Mandarin orange fruits are small 40–80 millimetres (1.6–3.1 in).[1] Their colour is orange, yellow-orange, or red-orange.[3] The skin is thin and peels off easily.[1] Their easiness to peel is an important advantage of mandarin oranges over other citrus fruits.[3] Just like with other citrus fruits, the endocarp (inner flesh) is separated into segments, which in their turn consist of a large number of elongated cells.[1] The fruits may be seedless or contain a small number of seeds. Mandarin orange fruits are sweet to taste, and can be eaten as whole or squeezed to make juice.[1][3]

In 2020, world production of mandarin oranges (combined with tangerines, clementines, and satsumas in reporting to FAOSTAT) was 38.6 million tonnes, led by China with 60% of the global total.[10] Spain produced more than two million tonnes in 2020, while other significant producers with around one million tonnes each were Turkey, Egypt and Morocco.[10]

Mandarin oranges, raw

Nutritional value per 100 g (3.5 oz)
Energy	223 kJ (53 kcal)
Carbohydrates	13.34 g
Sugars	10.58 g
Dietary fibre	1.8 g
Fat	0.31 g
Protein	0.81 g
Vitamins	Quantity %DV†
Vitamin A equiv. beta-Carotene	4% 34 μg 1% 155 μg
Thiamine (B1)	5% 0.058 mg
Riboflavin (B2)	3% 0.036 mg
Niacin (B3)	3% 0.376 mg
Pantothenic acid (B5)	4% 0.216 mg
Vitamin B6	6% 0.078 mg
Folate (B9)	4% 16 μg
Choline	2% 10.2 mg
Vitamin C	32% 26.7 mg
Vitamin E	1% 0.2 mg
Minerals	Quantity %DV†
Calcium	4% 37 mg
Iron	1% 0.15 mg
Magnesium	3% 12 mg
Manganese	2% 0.039 mg
Phosphorus	3% 20 mg
Potassium	4% 166 mg
Sodium	0% 2 mg
Zinc	1% 0.07 mg
Other constituents	Quantity
Water	85.2 g
Link to USDA Database entry
Units μg = micrograms • mg = milligrams IU = International units
†Percentages are roughly approximated using US recommendations for adults. Source: USDA FoodData Central

A mandarin orange contains 85% water, 13% carbohydrates, and negligible amounts of fat and protein (table). Among micronutrients, only vitamin C is in significant content (32% of the Daily Value) in a 100-gram reference serving, with all other nutrients in low amounts.

Mandarin fruitlets

During Chinese New Year, mandarin oranges/tangerine/satsumas are considered traditional symbols of abundance and good fortune. During the two-week celebration, they are frequently displayed as decoration and presented as gifts to friends, relatives, and business associates. Mandarin oranges, particularly from Japan, are a Christmas tradition in Canada, the United States, the United Kingdom and Russia.

In Canada and the United States, they are commonly purchased in 5- or 10-pound boxes,[3] individually wrapped in soft green paper, and given in Christmas stockings. This custom goes back to the 1880s, when Japanese immigrants in Canada and the United States began receiving Japanese mandarin oranges from their families back home as gifts for the New Year. The tradition quickly spread among the non-Japanese population, and eastwards across the country: each November harvest, "The oranges were quickly unloaded and then shipped east by rail. 'Orange Trains' – trains with boxcars painted orange – alerted everyone along the way that the irresistible oranges from Japan were back again for the holidays. For many, the arrival of Japanese mandarin oranges signaled the real beginning of the holiday season."[12] This Japanese tradition merged with European traditions related to the Christmas stocking. Saint Nicholas is said to have put gold coins into the stockings of three poor girls so that they would be able to afford to get married.[13] Sometimes the story is told with gold balls instead of bags of gold, and oranges became a symbolic stand-in for these gold balls, and are put in Christmas stockings in Canada[13][14] along with chocolate coins wrapped in gold foil.

Satsumas were also grown in the United States from the early 1900s, but Japan remained a major supplier.[15] U.S. imports of these Japanese oranges was suspended due to hostilities with Japan during World War II.[12] While they were one of the first Japanese goods allowed for export after the end of the war, residual hostility led to the rebranding of these oranges as "mandarin" oranges.[12]

The delivery of the first batch of mandarin oranges from Japan in the port of Vancouver, British Columbia (Canada), is greeted with a festival that combines Santa Claus and Japanese dancers[14]—young girls dressed in traditional kimono.[16]

Historically, the Christmas fruit sold in North America was mostly Dancys, but now it is more often a hybrid.[17]

Mandarins are one of the core ancestral citrus taxa, and are thought to have evolved in regions including South China and Japan in East Asia, and Vietnam in Southeast Asia.[19][5] 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,[20] the southern subspecies) and the genetically distinct and only distantly-related Mangshanyegan. The wild mandarins were found to be free of the introgressed pomelo (C. maxima) DNA found in domestic mandarins but they did appear to have small amounts (~1.8%) of introgression from the ichang papeda, which grows wild in the same region.[21]

The Nanling Mountains are also 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.[21] All tested domesticated cultivars were found to belong to one of these two genetic clusters, with varieties such as Nanfengmiju, Kishu and Satsuma deriving from the northern domestication event producing larger, redder fruit, while Willowleaf, Dancy, Sunki, Cleopatra, King, Ponkan, and others derived from the smaller, yellower-fruited southern cluster.[21]

The Tanaka classification system divided domestic mandarins and similar fruit into numerous species, giving distinct names to cultivars such as willowleaf mandarins (C. deliciosa), satsumas (C. unshiu), tangerines (C. tangerina). Under the Swingle system, all these are considered to be varieties of a single species, Citrus reticulata.[22] Hodgson represented them as several subgroups: common (C. reticulata), Satsuma, King (C. nobilis), Mediterranean (willowleaf), small-fruited (C. indica, C. tachibana and C. reshni), and mandarin hybrids.[23] In the genomic-based species taxonomy of Ollitrault et al., only pure 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 C. aurantium.[24]

Genetic analysis is consistent with continental mandarins representing a single species, with much of the variation within mandarins being due to hybridization.[2] A separate species, Citrus ryukyuensis that diverged from the mainland species between 2 and 3 million years ago when cut off by rising sea levals was found growing on the island of Okinawa, and its natural and agricultural hybridization with the mainland mandarin species has produced some of the unique island mandarin cultivars of Japan and Taiwan, such as the Tachibana orange,[20] previously classified as a subspecies of pure mandarin[2] before its parent was identified, and the Shekwasha.[20] Some of the small number of cultivars were found to be pure in initial gemonic analysis, including Sun Chu Sha mandarin[19][2] and Nanfengmiju,[25] but Wang detected in them not only an apparent Ichang papeda introgression found in all examined mandarins but also the distinct pomelo DNA of the domesticated mandarins.[21] Following initial hybridization, natural or cultivated backcrosses of the initial mandarin-pomelo hybrids with the mandarin stock produced mandarins with limited pomelo contribution,[2] that differed between the northern and southern domesticates.[21] An 'acidic' group of cultivars including Sunki and Cleopatra mandarins that likewise previously were thought to be pure but since found to contain small regions of introgressed pomelo DNA are too sour to be edible, but are widely used as rootstock and grown for juice.[22][2] Another group of mandarins, including some tangerines, Satsuma and King mandarins, show a greater pomelo contribution and derive from the limited-pomelo hybrids being crossed again, with sweet orange or pomelo, and likewise backcrossing in some cases, producing cultivars with moderate to high levels of pomelo introgression.[2] Hybrid mandarins thus fall on a continuum of increasing pomelo contribution with clementines, sweet and sour oranges, and grapefruit.[19] Mandarins and their hybrids are sold under a variety of names.

• Japanese citrus
• List of citrus fruits
• Tangerine
• Citrus unshiu
• Ju Song – "In Praise of the Orange-Tree"
• Orange (fruit)

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Data related to Citrus reticulata at Wikispecies