Orange

Plant Characteristics

Lifespan:	⌛	[[Lifespan::Perennial]]

Cultivation

Exposure:	☼	Sun"Sun" is not in the list (sun, part-sun, shade, unknown) of allowed values for the "Exposure" property., Indoors"Indoors" is not in the list (sun, part-sun, shade, unknown) of allowed values for the "Exposure" property.
Water:	◍	regular"regular" is not in the list (wet, moist, moderate, dry, less when dormant) of allowed values for the "Water" property.
Features:	✓	Fruit, Fragrance
Sunset Zones:		8, 9, 12-27, indoors

Scientific Names

Rutaceae >

Citrus >

sinensis >

An orange—specifically, the sweet orange—is the citrus fruit Citrus sinensis (syn. Citrus aurantium L. var. dulcis L., or Citrus aurantium Risso) and its fruit. The orange is a hybrid of ancient cultivated origin, possibly between pomelo (Citrus maxima) and tangerine (Citrus reticulata). It is a small flowering tree growing to about 10 m tall with evergreen leaves, which are arranged alternately, of ovate shape with crenulate margins and 4–10 cm long. The orange fruit is a hesperidium, a type of berry.

Oranges originated in Southeast Asia. The fruit of Citrus sinensis is called sweet orange to distinguish it from Citrus aurantium, the bitter orange. In a number of languages, it is known as a "Chinese apple" (e.g. Dutch Sinaasappel, "China's apple", or "Apfelsine" in German). The name is thought to ultimately derive from the Dravidian word for the orange tree, with its final form developing after passing through numerous intermediate languages.

Fruit

All citrus trees are of the single genus Citrus, and remain largely interbreedable; that is, there is only one "superspecies" which includes grapefruits, lemons, limes and oranges. Nevertheless, names have been given to the various members of the genus, oranges often being referred to as Citrus sinensis and Citrus aurantium. Fruits of all members of the genus Citrus are considered berries because they have many seeds, are fleshy and soft, and derive from a single ovary. An orange seed is called a pip. The white thread-like material, attached to the inside of the peel is called pith.

Varieties

Persian orange

The Persian orange, grown widely in southern Europe after its introduction to Italy in the 11th century, was bitter. Sweet oranges brought to Europe in the 15th century from India by Portuguese traders, quickly displaced the bitter, and are now the most common variety of orange cultivated. The sweet orange will grow to different sizes and colours according to local conditions, most commonly with ten carpels, or segments, inside.

Some South East European tongues name orange after Portugal, which was formerly the main source of imports of sweet oranges. Examples are Bulgarian portokal [портокал], Greek portokali [πορτοκάλι], Romanian portocală and Georgian phortokhali [ფორთოხალი]. Also in South Italian dialects (Neapolitan), orange is named portogallo or purtualle, literally "the Portuguese ones". Related names can also be found in non-European languages: Turkish Portakal, Arabic al-burtuqal [البرتقال], Persian porteghal [پرتقال] and Amharic birtukan.

Portuguese, Spanish, Arab, and Dutch sailors planted citrus trees along trade routes to prevent scurvy. On his second voyage in 1493, Christopher Columbus brought the seeds of oranges, lemons and citrons to Haiti and the Caribbean. They were introduced in Florida (along with lemons) in 1513 by Spanish explorer Juan Ponce de Leon, and were introduced to Hawaii in 1792.

Navel orange

A peeled sectioned navel orange. The underdeveloped twin is located on the bottom right.

A single mutation in 1820 in an orchard of sweet oranges planted at a monastery in Brazil yielded the navel orange, also known as the Washington, Riverside, or Bahie navel. The mutation causes navel oranges to develop a second orange at the base of the original fruit, opposite the stem. The second orange develops as a conjoined twin in a set of smaller segments embedded within the peel of the larger orange. From the outside, the smaller, and undeveloped twin leaves a formation at the bottom of the fruit that looks similar to the human navel.

Because the mutation left the fruit seedless and, therefore, sterile, the only means available to cultivate more of this new variety is to graft cuttings onto other varieties of citrus tree. Two such cuttings of the original tree were transplanted to Riverside, California in 1870, which eventually led to worldwide popularity.

Today, navel oranges continue to be produced via cutting and grafting. This does not allow for the usual selective breeding methodologies, and so not only do the navel oranges of today have exactly the same genetic makeup as the original tree, and are therefore clones; in a sense, all navel oranges can be considered to be the fruit of that single, over a century-old tree.

On rare occasions, however, further mutations can lead to new varieties.

Valencia orange

The Valencia or Murcia orange is one of the sweet oranges used for juice extraction. It is a late-season fruit, and therefore a popular variety when the navel oranges are out of season. For this reason, the orange was chosen to be the official mascot of the 1982 FIFA World Cup, which was held in Spain. The mascot was called "Naranjito" ("little orange"), and wore the colours of the Spanish soccer team uniform.

Blood orange

Orange output in 2005

The blood orange has streaks of red in the fruit, and the juice is often a dark burgundy colour. The fruit has found a niche as an interesting ingredient variation on traditional Seville marmalade, with its striking red streaks and distinct flavour. The scarlet navel is a variety with the same diploid mutation as the navel orange.

Propagation

Grafting, cuttings for true offspring. Seed.

Uses

Fruit, juice, marmelade. Oil from peel. Orange peel is used by gardeners as a slug repellent. Orange leaves can be boiled to make tea.

Gallery

• 

  These varieties are called 'Ambersweet' oranges.

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  Featured here are orange seeds (pips).

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  Navel oranges from Florida are the most common to be sold in US grocery stores.

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  Satsuma Oranges picked on Christmas day 2007 in Gainesville, Florida

References

• McPhee, John. Oranges (1966) - focuses on Florida groves.
• Sackman, Douglas Cazaux. Orange Empire: California and the Fruits of Eden (2005) comprehensive, multidimensional history of citrus industry in California
• Train, John. Oranges (2006)