The mandarin tree may be much smaller than that of the sweet orange or equal in size, depending on variety. With great age, some may reach a height of 25 ft (7.5 m) with a greater spread. The tree is usually thorny, with slender twigs, broad-or slender-lanceolate leaves having minute, rounded teeth, and narrowly-winged petioles. The flowers are borne singly or a few together in the leaf axils. The fruit is oblate, the peel bright-orange or red-orange when ripe, loose, separating easily from the segments. Seeds are small, pointed at one end, green inside. The Origin and Distribution of the mandarin orange is considered a native of south-eastern Asia and the Philippines. It is most abundantly grown in Japan, southern China, India, and the East Indies, and is esteemed for home consumption in Australia.
The commercial cultivation of mandarin oranges in the United States has developed mostly in Alabama, Florida and Mississippi and, to a lesser extent, in Texas, Georgia and California. Mexico has overproduced tangerines, resulting in low market value and cessation of plantings. The 1971-72 crop was 170,000 MT, of which, 8,600 MT were exported to the United States and lesser amounts to East Germany, Canada and Argentina. There is limited culture in Guatemala and some other areas of tropical America. These fruits have never been as popular in western countries as they are in the Orient, Coorg, a mountainous region of the Western Ghats, in India, is famous for its mandarin oranges. For commercial exploitation, mandarins have several disadvantages: the fruit has poor holding capacity on the tree, the peel is tender and therefore the fruits do not stand shipping well, and the tree has a tendency toward alternate bearing.
The suitable climate for Mandarin oranges are much more cold-hardy than the sweet orange, and the tree is more tolerant of drought. The fruits are tender and readily damaged by cold. Malaysia like Thailand and Philipines and Indonesia has almost similar climate and the Mandarin Orange able to grow well with proper technology. There were a huge area in Samarahan , Sarawak and Dungun , Terengganu grown with this citrus in early 1990'ies but due to various diseases and pests the hectarage reduces tremendously. Only certain resistant varieties left for domestic production. There are 6 registered Mandarin Orange varieties with Department of Agriculture Malayasia namely M17, M 25, M 28, M 31, M 32 and M 33. The most popular varieties grown today are M 33 registered by Mr Robert Wong Sai Kow from Jementah, Segamat, Johor in July 1989.
Class I are called Mandarin with few varieties.
(1) 'Changsa'–brilliant orange-red; sweet, but insipid; seedy. Matures early in the fall. The tree has high cold resistance; has survived 4º F (-15.56º C). It is grown as an ornamental.
(2) 'Le-dar'–arose from a climbing branch discovered on an 'Ellendale Beauty' mandarin tree in Bundaberg, Queensland, Australia, about 1959. The owners, named Darrow, took bud-wood from the branch and found that it retained its climbing tendency. Commercial propagation was undertaken by Langbecker Nurseries and the name was trademarked in 1965 when over 5,000 budded trees were put on sale. The budded trees produced large fruits, of rich color and high quality, maturing a little later than the parent.
(3) 'Emperor'–believed to have originated in Australia, and a leading commercial cultivar there; oblate, large, 2 1/2 in (6.5 cm) wide, 1 3/4 in (4.5 cm) high; peel pale-orange, medium thin; pulp pale-orange; 9-10 segments; seeds long, pointed, 10-16 in number. Midseason. Grown on rough lemon rootstock or, better still, on Poncirus trifoliata.
(4) 'Oneco'–closely related to 'Emperor'; from northwestern India; introduced into Florida by P.W. Reasoner in 1888. Oblate to faintly pear-shaped; medium to large, 2 1/2-3 1/2 in (6.25-9 cm) wide, 2 1/4-3 in (5.7-7.5 cm) high; peel orange-yellow, glossy, rough and puffy; pulp orange-yellow, of rich, sweet flavor; 5-10 seeds. Medium to late in season. Tree large and vigorous, high-yielding.
(5) 'Willow-leaf'–(China Mandarin')–oblate to rounded, of medium size, 2-2 1/2 in (5-6.25 cm) wide, 1 3/4-2 1/4 in (4.5-5.7 cm) high; peel orange, smooth, glossy, thin; pulp orange, with 10-12 segments; very juicy, of sweet, rich flavor; 15-20 seeds. Early in season. Tree is small to medium, with very slender, willowy branches, almost thornless, and slim leaves. Reproduces true from seed. Grown mainly as an ornamental and for breeding.
Class II known as Tangerine with 6 different varieties as follows:-
(1)'Clementine' (Algerian Tangerine')–introduced into Florida by the United States Department of Agriculture in 1909 and from Florida into California in 1914; also brought directly from the Government Experiment Station in Algeria about the same time; round to elliptical; of medium size, 2-2 3/8 in (5-6.1 cm) wide, 2-2 3/4 in (5-7 cm) high; peel deep orange-red, smooth, glossy, thick, loose, but scarcely puffy; pulp deep-orange with 8-12 segments; juicy, and of fine quality and flavor; 3-6 seeds of medium size, non-nucellar; season early but long, extending into the summer. Tree is of medium size, almost thornless; a shy bearer. In Spain it has been found that a single application of gibberellic acid at color-break, considerably reduces peel blemishes and permits late harvesting. 'Clementine' crossed with pollen of the 'Orlando' tangelo produced the hybrid selections, 'Robinson', 'Osceola', and 'Lee', released in 1959. The last two are no longer grown as fruit crops; only utilized in breeding programs.
(2) 'Cleopatra' ('Ponki', or 'Spice')–(now being shown as Citrus reshni Hort. ex Tanaka)–introduced into Florida from Jamaica before 1888; oblate, small; peel dark orange-red; pulp of good quality but seedy. Fruits too small to be of commercial value; they remain on the tree until next crop matures, adding to the attractiveness of the tree which is itself highly ornamental; much used as a rootstock in Japan and Florida.
(3) Dancy'–may have come from China; found in the grove of Col. G.L. Dancy at Buena Vista, Florida, and brought into cultivation in 1871 or 1872. Oblate to pear-shaped; of medium size, 2 1/4-3 in (5.7-7.5 cm) wide, 1 1/2-2 1/8 in (4-5.4 cm) high; peel deep orange-red to red, smooth, glossy at first but lumpy and fluted later, thin, leathery, tough; pulp dark-orange with 10-14 segments, of fine quality, richly flavored; 6-20 small seeds. In season in late fall and winter. This is the leading tangerine in the United States, mainly grown in Florida, secondarily in California, and, to a small extent, in Arizona. Tree is vigorous, cold-tolerant, bears abundantly. Alternate-bearing induced by an abnormally heavy crop, can be avoided by spraying with a chemical thinner (Ethephon) when the fruits are very young. Thinning enhances fruit size and market value. This cultivar is disease-resistant but highly susceptible to chaff scale (Parlatoria pergandii) which leaves green feeding marks on the fruit making it unmarketable. Control can be achieved by spring and summer or spring and fall spraying of an appropriate pesticide.
(4) 'Ponkan' ('Chinese Honey Orange')–round to oblate; large, 2 3/4-3 3/16 in (7-8 cm) wide; peel orange, smooth, furrowed at apex and base; medium thick; pulp salmon-orange, melting, with 9-12 segments, very juicy, aromatic, sweet, of very fine quality and with few seeds. Tree not as cold-hardy as 'Dancy', small, upright; can be maintained as a "dwarf' and in China, where the fruit is greatly prized, may be planted 900 to the acre (2,224/ha). R.C. Pitman, Jr., of Apopka, Florida, organized the Florida Ponkan Corporation in 1948, served as its President, and has continuously promoted the culture of this delicious fruit.
(5) 'Robinson'–the result of pollinating the 'Clementine' tangerine with the 'Orlando' tangelo, at the United States Department of Agriculture's Horticultural Field Station, Orlando, Florida, was introduced into cultivation in 1960. It is essentially a tangerine, has 10 to 20 seeds. Back-crossing with pollen of the 'Orlando' greatly elevates fruit-set but also results in increasing the seed count to an average of 22 per fruit. This cultivar had lost popularity with growers but the recent practice of spraying with Ethrel (a ripening agent) to speed up coloring on the tree and loosen the fruit has been such an important advance in harvesting and in reducing time in the coloring room that it has reinstated the 'Robinson' as a commercial cultivar. In 1980, the crop forecast was 1.1 million boxes, about 40% of that of 'Dancy'.
(6) 'Sunburst'–This cultivar was selected in 1967 from 15 seedlings; of hybrids of 'Robinson' and 'Osceola', the latter being another 'Clementine' pollinated with 'Orlando' tangelo but still dominantly a tangerine. 'Sunburst' was propagated on several rootstocks in 1970 and released in Florida in 1979. Oblate, medium-sized, 2 1/2-3 in (6.25-7.5 cm) wide; peel is orange to scarlet in central Florida, orange around the Indian River area; pulp in 11-15 segments with much colorful juice; seeds 10 to 20 according to degree of pollination; green inside. Matures in a favorable season: (mid-November to mid-December). Tree vigorous, thornless, early-bearing, self-infertile; needs cross-pollination for good fruit set; amenable to sour orange, rough lemon, 'Carrizo' and 'Cleopatra' root-stocks though the latter results in slightly reduced fruit size; medium cold-hardy; resistant to Alternaria and very tolerant of snow scale.
Class III, Satsuma (sometimes marketed as "Emerald Tangerine")
The Satsuma orange is believed to have originated in Japan about 350 years ago as a seedling of a cultivar, perhaps the variable 'Zairi'. It is highly cold-resistant; has survived 12º F (-11.11º C); is more resistant than the sweet orange to canker, gummosis, psorosis and melanose. It is budded onto Poncirus trifoliata in Florida, sweet orange in California. It has been found in Spain that spraying with gibberellic acid 4 to 5 weeks before commercial maturity prevents puffiness, delays ripening, and permits harvesting 2 months later than normal, but this leads to reduced yields the following year.
(1) 'Owari'–oblate to rounded or becoming pear-shaped with age; of medium size, 1 1/2-2 3/4 in (4-6.1 cm) wide, 1 1/2-2 1/2 in (4-6.25 cm) high; peel orange, slightly rough, becoming lumpy and fluted, thin, tough; pulp orange, of rich, subacid flavor; nearly seedless, sometimes 1-4 seeds. Early but short season. Peel often remains more or less green after maturity and needs to be artificially colored in order to market before loss of flavor. Tree small, almost thornless, large-leaved, with faint or no wings on petioles; cultivated commercially in northern Florida, Alabama and other Gulf States; very little in California.
(2) 'Wase'–Discovered at several sites in Japan from before 1895; believed to be a bud sport of 'Owari'; was propagated and extensively planted in Japan before 1910; was growing in Alabama in 1917; one tree was sent to California in 1929; oblate to rounded or somewhat conical; large, 2 1/3 in (5.81 cm) wide, 1 3/4 in (4.5 cm) high; peel orange, thin, smooth; pulp salmon-orange, melting, sweet, with 10 segments more or less. Very early in season. Tree is dwarf, slow-growing, heavy-bearing, but susceptible to pests and diseases
(3) 'Kara' ('Owari' X 'King' tangor)–a hybrid developed at the California Citrus Experiment Station and distributed in 1935; sub-oblate or nearly round; of medium size, 2 1/8-3 in (5.4-7.5 cm) wide, 2 1/8-2 3/4 in (5.4-7 cm) high; peel deep-orange to orange-yellow, lumpy and wrinkled at apex, puffy with age, thin to medium, fairly tough; pulp deep yellow-orange, with 10-13 segments, tender, very juicy, aromatic, of rich flavor, acid until fully ripe, then sweet; usually 12-20 large seeds, at times nearly seedless. Late in season. Tree is vigorous, thornless, with large leaves, the petiole narrowly winged.
During Chinese New Year Festival in early February every year, millions of mandrarin orange imported from China to Malaysia. The fruit was packed in various packaging system to gain extra value for money. Many races consume the Mandarin Orange imported from China with a low price and medium quality fruits. During this period of time the local fruit and vegetable receive a very low price and farmers income are severely affected. Out of 34-26 million of Mandarin production in the world about 16 million metric ton (56%) are from China. Other countries producing huge number of mandarin orange were Spain, Brazil, Japan, South Korea, Pakistan, Morocco, Egypt, Turkey and Thailand. Most of this fruit are for export to various nation world wide.