Difference between revisions of "Citrus"

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{{Taxobox
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__NOTOC__{{Plantbox
| color = lightgreen
 
 
| name = ''Citrus''
 
| name = ''Citrus''
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| common_names = Citrus
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| growth_habit = small tree or large shrub
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| high = ?  <!--- 1m (3 ft) -->
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| wide =    <!--- 65cm (25 inches) -->
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| origin = ?  <!--- Mexico, S America, S Europe, garden, etc -->
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| poisonous =    <!--- indicate parts of plants which are known/thought to be poisonous -->
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| lifespan =    <!--- perennial, annual, etc -->
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| exposure = ?  <!--- full sun, part-sun, semi-shade, shade, indoors, bright filtered (you may list more than 1) -->
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| water = ?  <!--- frequent, regular, moderate, drought tolerant, let dry then soak -->
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| features =    <!--- flowers, fragrance, fruit, naturalizes, invasive -->
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| hardiness =    <!--- frost sensitive, hardy, 5°C (40°F), etc -->
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| bloom =    <!--- seasons which the plant blooms, if it is grown for its flowers -->
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| usda_zones = ?  <!--- eg. 8-11 -->
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| sunset_zones =    <!--- eg. 8, 9, 12-24, not available -->
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| color = IndianRed
 
| image = OrangeBloss wb.jpg  
 
| image = OrangeBloss wb.jpg  
| image_width = 240px
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| image_width = 240px   <!--- leave as 240px if horizontal orientation photo, or change to 180px if vertical -->
| image_caption = ''Citrus reticulata''
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| image_caption =     <!--- eg. Cultivated freesias -->
| regnum = [[Plant]]ae
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| regnum = Plantae
| divisio = [[flowering plant|Magnoliophyta]]
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| divisio = Magnoliophyta
| classis = [[dicotyledon|Magnoliopsida]]
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| classis = Magnoliopsida
| subclassis = [[Rosidae]]
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| subclassis = Rosidae
| ordo = [[Sapindales]]
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| ordo = Sapindales
| familia = [[Rutaceae]]
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| familia = Rutaceae
| genus = '''''Citrus'''''
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| genus = Citrus
| genus_authority = [[Carolus Linnaeus|L.]]
 
| subdivision_ranks = Species & major hybrids
 
| subdivision =
 
'''Species'''<br />
 
''[[Key lime|Citrus aurantifolia]]'' - Key lime <br />
 
''[[Pomelo|Citrus maxima]]'' - Pomelo<br />
 
''[[Citron|Citrus medica]]'' - Citron<br />
 
''[[Mandarin orange|Citrus reticulata]]'' - Mandarin & [[Tangerine]]<br />
 
'''Major hybrids'''<br />
 
''[[Orange (fruit)|Citrus ×sinensis]]'' - Sweet Orange<br />
 
''[[Bitter orange|Citrus ×aurantium]]'' - Bitter Orange<br>
 
''[[Grapefruit|Citrus ×paradisi]]'' - Grapefruit<br />
 
''[[Lemon|Citrus ×limon]]'' - Lemon<br />
 
''[[Rangpur lime|Citrus ×limonia]]'' - Rangpur lime<br />
 
''[[Persian lime|Citrus ×latifolia]]'' - Persian lime <br />
 
'''See also main text for other hybrids'''
 
 
}}
 
}}
'''''Citrus''''' is a common term and [[genus]] of [[flowering plant]]s in the family [[Rutaceae]], originating in tropical and subtropical southeast [[Asia]]. The plants are large [[shrub]]s or small [[tree]]s, reaching 5–15 m tall, with [[spine (biology)|spiny]] shoots and alternately arranged [[evergreen]] [[leaf|leaves]] with an entire margin. The [[flower]]s are solitary or in small [[corymb]]s, each flower 2–4 cm diameter, with five (rarely four) white petals and numerous stamens; they are often very strongly scented. The [[fruit]] is a ''[[hesperidium]]'', a specialised berry, globose to elongated, 4–30 cm long and 4–20 cm diameter, with a leathery rind surrounding segments or "liths" filled with pulp [[vesicle]]s. The genus is commercially important as many species are cultivated for their fruit, which is eaten fresh or pressed for [[juice]].
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{{Inc|
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[[Image:Citrus fruits.jpg|250px|thumb|left|Citrus fruits]]
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Citrus (ancient name of a fragrant African wood, afterward transferred to the Citron). Rutaceae. Citron. Lemon. Orange. Small evergreen, more or less spiny trees or shrubs, grown for their edible fruits, and also attractive in foliage and flower.
  
Citrus fruits are notable for their fragrance, partly due to [[flavonoids]] and [[limonoids]] (which in turn are [[terpene]]s) contained in the rind, and most are juice-laden. The juice contains a high quantity of [[citric acid]] giving them their characteristic sharp flavour. They are also good sources of [[vitamin C]] and [[flavonoid]]s.
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Leaves glandular-dotted, persistent, apparently simple (in reality unifoliate compound lvs.), borne on more or less winged or margined petioles, which are usually articulated with the blade and at their attachment to the twig: spines usually present, borne singly at the side of the bud in the axils of the lvs.: fls. clustered or rarely solitary in the axils of the lvs., or in small lateral or terminal cymes or panicles, white or pinkish purple in the bud; petals 5 (rarely 4 or 6) thick, strap-shaped, not clawed at the base, imbricated; stamens numerous (16-60, usually 20-40) at least four times as many as the petals, polyadelphous, cohering toward the bases in a few bundles; ovary 8-15-celled, with a prominent usually deciduous style containing as many tubes as there are cells in the ovary: fr. a hes- peridium, globose, oval or oblate-spheroid, the segms. filled with juicy pulp composed of stalked pulp-vesicles; seeds 1-8 in a cell, oval or oblong, ¼-¾in. long, with a pergameneous testa and thick fleshy cotyledons, usually with adventive embryos arising as buds from the nucellar tissue of the mother plant. Natives of Trop. and Subtrop. Asia and the Malayan Archipelago.— Half a dozen species are commonly cult. and have given rise to very many varieties as well as numerous hybrids, making the delimitation of the species exceedingly difficult. See Citrange, Citron, Etrog, Grapefruit, Lemon, Lime, Limequat, Orange, Pomelo, Tangelo.
  
The taxonomy of the genus is complex and the precise number of natural species is unclear, as many of the named species are clonally-propagated hybrids, and there is genetic evidence that even the wild, true-breeding species are of hybrid origin. Cultivated ''Citrus'' may be derived from as few as four ancestral species. Numerous natural and cultivated origin [[hybrid]]s include commercially important [[fruit]] such as the [[orange (fruit)|orange]], [[lemon]], [[lime (fruit)|lime]], [[grapefruit]], and some [[tangerine]]s. Recent research has suggested that the closely related genus ''[[Fortunella]]'', and perhaps also ''[[Poncirus]]'' and the Australian genera ''[[Microcitrus]]'' and ''[[Eremocitrus]]'', should be included in ''Citrus''. In fact, most botanists now classify ''Microcitrus'' and ''Eremocitrus'' as part of the genus ''Citrus''.
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The nomenclature here followed is based on the writer's treatment of the species of Citrus in "Plantae Wilsonianae." The fewest possible number of changes have been made consistent with presenting a clear account of the genus. A careful study of Citrus and the genera most nearly related to it has shown that the trifoliate orange differs in so many and such important characters that it seems necessary to recognize it as a separate genus (Poncirus). The same is true of the kumquats and the Australian limes.
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{{SCH}}
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}}
  
== Cultivation ==
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==Cultivation==
{{further|[[Citrus production]]}}
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{{edit-cult}}<!--- Type cultivation info below this line, then delete this entire line -->
As citrus trees [[hybrid]]ise very readily (e.g., seeds grown from [[Persian lime]]s can produce fruit similar to grapefruit), all commercial citrus cultivation uses trees produced by [[grafting]] the desired fruiting [[cultivar]]s onto rootstocks selected for disease resistance and hardiness.
 
  
The color of citrus fruits only develops in climates with a (diurnal) cool winter. In tropical regions with no winter, citrus fruits remain green until maturity, hence the tropical "green orange". The lime plant in particular is extremely sensitive to cool conditions, thus it is usually never exposed to cool enough conditions to develop a color. If they are left in a cool place over winter, the fruits will actually change to a yellow color. Many citrus fruits are picked while still green, and ripened while in transit to supermarkets.
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===Propagation===
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{{edit-prop}}<!--- Type propagation info below this line, then delete this entire line -->
  
[[Image:Citrus fruit
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===Pests and diseases===
s.jpg|250px|thumb|left|Citrus fruits]]
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{{edit-pests}}<!--- Type pest/disease info below this line, then delete this entire line -->
Citrus trees are not generally frost hardy. ''Citrus reticulata'' tends to be the hardiest of the common Citrus species and can withstand short periods down to as cold as −10 °C, but realistically temperatures not falling below −2 °C are required for successful cultivation. A few hardy hybrids can withstand temperatures well below freezing, but do not produce quality fruit. A related plant, the [[Trifoliate orange]] (''Poncirus trifoliata'') can survive below −20 °C; its fruit are astringent and inedible unless cooked.
 
  
The trees do best in a consistently sunny, humid environment with fertile soil and adequate rainfall or irrigation. (Older 'abandoned' Citrus in low valleyland may suffer, yet survive, the dry summer of Central California Inner Coast Ranges. Any age Citrus grows well with infrequent irrigation in partial/understory shade, but the fruit crop is smaller.) Though broadleaved, they are evergreen and do not drop leaves except when stressed. The trees flower (sweet-scented at 2 to 20 meters) in the spring, and fruit is set shortly afterward. Fruit begins to ripen in fall or early winter months, depending on cultivar, and develops increasing sweetness afterward. Some cultivars of tangerines ripen by winter. Some, such as the grapefruit, may take up to eighteen months to ripen.
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==Species==
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*''[[Key lime|Citrus aurantifolia]]'' - Key lime
 +
*''[[Pomelo|Citrus maxima]]'' - Pomelo
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*''[[Citron|Citrus medica]]'' - Citron
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*''[[Mandarin orange|Citrus reticulata]]'' - Mandarin & [[Tangerine]]
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* ''[[Citrus halimii]]'', a more recent discovery, from [[Thailand]] and [[Malaya]]
  
[[Image:Limes.jpg|250px|thumb|right|Limes in a grocery store.]]
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Major hybrids:
Major commercial citrus growing areas include southern [[China]], the [[Mediterranean Basin]] (including [[Spain|Southern Spain]]), [[South Africa]], [[Australia]], the southernmost [[United States]], and parts of [[South America]]. In the [[United States|U.S.]], [[Florida]], [[Texas]], and [[California]] are major producers, while smaller plantings are present in other [[Sun Belt]] states.
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*''[[Orange (fruit)|Citrus ×sinensis]]'' - Sweet Orange
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*''[[Bitter orange|Citrus ×aurantium]]'' - Bitter Orange
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*''[[Grapefruit|Citrus ×paradisi]]'' - Grapefruit
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*''[[Lemon|Citrus ×limon]]'' - Lemon
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*''[[Rangpur lime|Citrus ×limonia]]'' - Rangpur lime
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*''[[Persian lime|Citrus ×latifolia]]'' - Persian lime
  
Citrus trees grown in tubs and wintered under cover were a feature of [[History of gardens|Renaissance gardens]], once glass-making technology enabled sufficient expanses of clear glass to be produced. The ''Orangerie'' at the [[Louvre|Palace of the Louvre]], 1617, inspired imitations that were not eclipsed until the development of the modern greenhouse in the 1840s. An [[orangery]] was a feature of royal and aristocratic residences through the 17th and 18th centuries. In the United States the earliest surviving orangery is at the Tayloe House, Mount Airy, Virginia.
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{{Inc|
 
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*C. bergamia, Risso. [[Bergamot]]. A small tree: lvs. oblong-oval, with long, winged petioles: fls. small, white, very fragrant: fruits pyriform, 3-4 in. diam., thin-skinned, pale yellow when ripe; pulp acid; seeds oblong, many. Extensively cult. in Calabria for the essential oil which is expressed from the peel and used in making Eau de Cologne and other perfumes.
Some modern hobbyists still grow dwarf citrus in containers or greenhouses in areas where it is too cold to grow it outdoors. Consistent climate, sufficient sunlight, and proper watering are crucial if the trees are to thrive and produce fruit. Compared to many "normal green" shrubs, citrus better-tolerates poor container care. For cooler winter areas, [[Lime (fruit)|lime]] and [[lemon]] should not be grown, since they are more sensitive to winter cold than other citrus fruits. Lemons are commercially grown in cooler-summer/moderate-winter coastal Southern California, because sweetness is neither attained nor expected in retail lemon fruit. Tangerines, tangors and [[yuzu]] can be grown outside even in regions with sub-zero winters, although this may affect fruit quality. Hybrids with kumquats ([[citrofortunella]]) have good cold resistance.
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*C. histrix, see [[Papeda]].
 
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*C. japonica, see [[Kumquat]].
=== Pests and diseases ===
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*C. taitensis, Risso. Otaheite Orange. A dwarf plant, having lemon-like fls. and lemon-shaped fr. orange in color with a mawkish taste. Commonly grown by florists as an ornamental pot-plant. Rarely used as a stock for dwarfing common citrous frs. This plant is not a native of Tahiti as the name would indicate, but is probably of hybrid origin.
[[Image:Clementinepeeled.jpg|thumb|250px|Clementines have thinner skins than oranges]]
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*C. trifoliate (syn. Poncirus trifoliata).
''Citrus'' plants are very liable to infestation by [[aphid]]s, [[whitefly]] and [[scale insect]]s (e.g. [[California red scale]]). Also rather important are the viral infections to which some of these [[ectoparasite]]s serve as [[vector (biology)|vectors]] such as the aphid-transmitted ''[[Citrus tristeza virus]]'' which when unchecked by proper methods of control is devastating to citrine plantations.
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{{SCH}}
The foliage is also used as a food plant by the [[larva]]e of some [[Lepidoptera]] species including [[Common Emerald]], [[Double-striped Pug]], [[Giant Leopard Moth]], ''[[Hypercompe|Hypercompe eridanus]]'', ''[[Hypercompe|Hypercompe icasia]]'' and ''[[Hypercompe|Hypercompe indecisa]]''. [[Helix_aspersa|European brown snail (Helix)]] can
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}}
be a problem in California, though [[Khaki_Campbell|laying]] female [[Mallard|Mallard-based]] [[Anas|(Anas)]] [[duck]]s eat snails and slugs. .
 
 
 
{{Main|List of citrus diseases}}
 
 
 
== Uses ==
 
=== Culinary ===
 
[[Image:Ambersweet oranges.jpg|thumb|250px|Oranges are used in many foods.]]
 
Many citrus fruits, such as [[orange (fruit)|oranges]], [[tangerine]]s, [[grapefruit]]s, and [[clementine]]s, are generally eaten fresh. They are typically peeled and can be easily split into segments. Grapefruit is more commonly halved and eaten out of the skin with a utensil. Orange and grapefruit juices are also very popular [[breakfast]] beverages. More astringent citrus, such as [[lemons]] and [[Lime (fruit)|limes]] are generally not eaten on their own. Though [[Meyer_Lemon|'Meyer' "Lemon"]] can be eaten 'out of hand', it is both sweet and sour. [[Lemonade]] or [[limeade]] are popular beverages prepared by diluting the juices of these fruits and adding sugar. Lemons and limes are also used as garnishes or in cooked dishes. Their juice is used as an ingredient in a variety of dishes, it can commonly be found in salad dressings and squeezed over cooked meat or vegetables. A variety of flavours can be derived from different parts and treatments of citrus fruits. The [[peel (fruit)|rind]] and [[essential oil|oil]] of the fruit is generally very bitter, especially when cooked. The fruit pulp can vary from sweet and tart to extremely sour. [[Marmalade]], a condiment derived from cooked orange and lemon, can be especially bitter. Lemon or lime is commonly used as a [[garnish]] for water, soft drinks, or cocktails. Citrus juices, rinds, or slices are used in a variety of mixed drinks. The skin of some citrus fruits, known as [[zest]], is used as a spice in cooking. The [[zest]] of a citrus fruit, preferably lemon or an orange, can also be soaked in water in a [[coffee]] filter, and drank.
 
 
 
=== Medical ===
 
Citrus juice also has medical uses - the lemon juice is used to relieve the pain of [[bee sting]]s. The orange is also used in [[Vitamin C]] [[pills]], which prevents scurvy. Scurvy is caused by Vitamin C deficiency, and can be prevented by having 10 milligrams of Vitamin C a day. An early sign of scurvy is fatigue. If ignored, later symptoms are bleeding and brusing easily.
 
 
 
== History ==
 
[[Image:Mandarin tree closeup.JPG|thumb|250px|right|Mandarin oranges, still on the tree]]
 
Prior to human cultivation, the genus ''Citrus'' originated in [[Southeast Asia]] and consisted of just a few species:
 
* ''[[Citrus maxima]]'', the pummelo, from the [[Malay archipelago]]
 
* ''[[Citrus medica]]'', the citron, from [[India]]
 
* ''[[Citrus aurantifolia]]'', the key lime, from [[India]]
 
* ''[[Citrus reticulata]]'', the mandarin and similar, from [[China]]
 
* ''[[Citrus halimii]]'', a more recent discovery, from [[Thailand]] and [[Malaya]]
 
 
 
{{sect-stub}}
 
  
== List of citrus fruits ==
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=== Varieties ===
 
[[Image:Pair of lemons.jpg|thumb|250px|right|Pair of lemons]]
 
[[Image:Pair of lemons.jpg|thumb|250px|right|Pair of lemons]]
 
* [[Alemow]], Colo, ''C. ×macrophylla''
 
* [[Alemow]], Colo, ''C. ×macrophylla''
Line 109: Line 98:
 
* [[Kumquat]] - in the related genus ''[[Fortunella]]'', not ''Citrus''; forms hybrids with ''Citrus'' (see ''[[Citrofortunella]]'')
 
* [[Kumquat]] - in the related genus ''[[Fortunella]]'', not ''Citrus''; forms hybrids with ''Citrus'' (see ''[[Citrofortunella]]'')
 
* [[Lemon]] ''Citrus ×limon''
 
* [[Lemon]] ''Citrus ×limon''
* [[Lime (fruit)|L
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* [[Lime (fruit)|Lime]] ''[[Citrus aurantifolia]]''
ime]] ''[[Citrus aurantifolia]]''
 
 
* [[Citrus limetta|limetta]], Sweet Lemon ''C. ×limetta''
 
* [[Citrus limetta|limetta]], Sweet Lemon ''C. ×limetta''
 
* [[Limequat]] ''Citrus'' ×''Fortunella'' [[hybrid]]s
 
* [[Limequat]] ''Citrus'' ×''Fortunella'' [[hybrid]]s
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* [[Yuzu]] ''C. ×junos''
 
* [[Yuzu]] ''C. ×junos''
  
[[Image:Lemon-edit1.jpg|right|thumb|250px|Lemon, whole and in section]]
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==Gallery==
== References ==
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<gallery>
* Freitas de Araújo, E., Paganucci de Queiroz, L., and Machado, M. A. 2003. What is ''Citrus''? Taxonomic implications from a study of cp-DNA evolution in the tribe Citreae (Rutaceae subfamily Aurantioideae). ''Organisms Diversity & Evolution'' 3(1): 55-62 (abstract online [http://www.ingentaconnect.com/content/urban/601/2003/00000003/00000001/art00058 here])
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Image:Limes.jpg|Limes in a grocery store
* Nicolosi, E., Z. N. Deng, A. Gentile, S. La Malfa, G. Continella, and E. Tribulato. 2000. ''Citrus'' phylogeny and genetic origin of important species as investigated by molecular markers. ''Theoretical and Applied Genetics'' 100(8): 1155 - 1166 (abstract online [http://www.springerlink.com/openurl.asp?genre=article&eissn=1432-2242&volume=100&issue=8&spage=1155 here]).
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Image:Clementinepeeled.jpg|Clementines have thinner skins than oranges
* Sackman. Douglas Cazaux. ''Orange Empire: California and the Fruits of Eden'' (2005) comprehensive, multidimensional history of citrus industry in California
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Image:Ambersweet oranges.jpg|Oranges are used in many foods.
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Image:Mandarin tree closeup.JPG|right|Mandarin oranges, still on the tree
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Image:Lemon-edit1.jpg|Lemon, whole and in section
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</gallery>
  
* {{cite book | author = Various authors | title=Citrus | year = 2002 | editor = Giovanni Dugo and Angelo Di Giacomo, eds. | publisher = Taylor & Francis | id = ISBN 0-415-28491-0}}
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==References==
** Calabrese, Francesco. "Origin and history".
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*[[Standard Cyclopedia of Horticulture]], by L. H. Bailey, MacMillan Co., 1963
* <sup>2</sup> [http://www.hort.purdue.edu/newcrop/tropical/lecture_32/lec_32.html Citrus fruits] from [[Purdue University]]
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<!--- xxxxx  *Flora: The Gardener's Bible, by Sean Hogan. Global Book Publishing, 2003. ISBN 0881925381  -->
* [http://www.corse.inra.fr/pub95/p95sr10.htm Citrus taxonomy (abstract)]
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<!--- xxxxx  *American Horticultural Society: A-Z Encyclopedia of Garden Plants, by Christopher Brickell, Judith D. Zuk. 1996. ISBN 0789419432  -->
 +
<!--- xxxxx  *Sunset National Garden Book. Sunset Books, Inc., 1997. ISBN 0376038608  -->
  
* [http://lib.ucr.edu/agnic/webber/ partial (Vols 1, 2, & Vol 5, Chap 5) online publ. of 1967-1989 (last revisions of each vol) "The Citrus Industry", University of California Board of Regents (UC Press)]. Full printed versions should be at your University library.
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==External links==
 +
*{{wplink}}
  
== External links ==
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{{stub}}
* [http://www.crec.ifas.ufl.edu/index.htm Citrus Research and Education Center] of [[IFAS]](largest citrus research center in world)
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[[Category:Categorize]]
* [http://www.uga.edu/fruit/citrus.htm Citrus] (Mark Rieger, Professor of Horticulture, University of Georgia)
 
* [http://www.plantnames.unimelb.edu.au/Sorting/Citrus_1.html Sorting Citrus names]
 
* [http://www.fundecitrus.com.br/english/menu_us.html Fundecitrus - Fund for Citrus Plant Protection] is an organization of citrus [[Brazil]]ian producers and processors.
 
* [http://www.homecitrusgrowers.co.uk/poncirustrifoliata/poncirus.html Home Citrus Growers]
 
  
[[Category:lists of foods|Citrus fruits]]
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<!--  in order to add all the proper categories, go to http://www.plants.am/wiki/Plant_Categories and copy/paste the contents of the page here, and then follow the easy instructions!    -->
[[Category:lists of plants]]
 
[[Category:Citrus| ]]
 
[[Category:Fruit]]
 
[[Category:Sapindales]]
 

Latest revision as of 21:03, 22 July 2009


OrangeBloss wb.jpg


Plant Characteristics
Origin: ?
Cultivation
Exposure: ?"?" is not in the list (sun, part-sun, shade, unknown) of allowed values for the "Exposure" property.
Water: ?"?" is not in the list (wet, moist, moderate, dry, less when dormant) of allowed values for the "Water" property.
Scientific Names

Rutaceae >

Citrus >



Read about Citrus in the Standard Cyclopedia of Horticulture 
Citrus fruits

Citrus (ancient name of a fragrant African wood, afterward transferred to the Citron). Rutaceae. Citron. Lemon. Orange. Small evergreen, more or less spiny trees or shrubs, grown for their edible fruits, and also attractive in foliage and flower.

Leaves glandular-dotted, persistent, apparently simple (in reality unifoliate compound lvs.), borne on more or less winged or margined petioles, which are usually articulated with the blade and at their attachment to the twig: spines usually present, borne singly at the side of the bud in the axils of the lvs.: fls. clustered or rarely solitary in the axils of the lvs., or in small lateral or terminal cymes or panicles, white or pinkish purple in the bud; petals 5 (rarely 4 or 6) thick, strap-shaped, not clawed at the base, imbricated; stamens numerous (16-60, usually 20-40) at least four times as many as the petals, polyadelphous, cohering toward the bases in a few bundles; ovary 8-15-celled, with a prominent usually deciduous style containing as many tubes as there are cells in the ovary: fr. a hes- peridium, globose, oval or oblate-spheroid, the segms. filled with juicy pulp composed of stalked pulp-vesicles; seeds 1-8 in a cell, oval or oblong, ¼-¾in. long, with a pergameneous testa and thick fleshy cotyledons, usually with adventive embryos arising as buds from the nucellar tissue of the mother plant. Natives of Trop. and Subtrop. Asia and the Malayan Archipelago.— Half a dozen species are commonly cult. and have given rise to very many varieties as well as numerous hybrids, making the delimitation of the species exceedingly difficult. See Citrange, Citron, Etrog, Grapefruit, Lemon, Lime, Limequat, Orange, Pomelo, Tangelo.

The nomenclature here followed is based on the writer's treatment of the species of Citrus in "Plantae Wilsonianae." The fewest possible number of changes have been made consistent with presenting a clear account of the genus. A careful study of Citrus and the genera most nearly related to it has shown that the trifoliate orange differs in so many and such important characters that it seems necessary to recognize it as a separate genus (Poncirus). The same is true of the kumquats and the Australian limes. CH


The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.


Cultivation

Do you have cultivation info on this plant? Edit this section!

Propagation

Do you have propagation info on this plant? Edit this section!

Pests and diseases

Do you have pest and disease info on this plant? Edit this section!

Species

Major hybrids:


Read about Citrus in the Standard Cyclopedia of Horticulture 
  • C. bergamia, Risso. Bergamot. A small tree: lvs. oblong-oval, with long, winged petioles: fls. small, white, very fragrant: fruits pyriform, 3-4 in. diam., thin-skinned, pale yellow when ripe; pulp acid; seeds oblong, many. Extensively cult. in Calabria for the essential oil which is expressed from the peel and used in making Eau de Cologne and other perfumes.
  • C. histrix, see Papeda.
  • C. japonica, see Kumquat.
  • C. taitensis, Risso. Otaheite Orange. A dwarf plant, having lemon-like fls. and lemon-shaped fr. orange in color with a mawkish taste. Commonly grown by florists as an ornamental pot-plant. Rarely used as a stock for dwarfing common citrous frs. This plant is not a native of Tahiti as the name would indicate, but is probably of hybrid origin.
  • C. trifoliate (syn. Poncirus trifoliata).

CH


The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.


Varieties

Pair of lemons

Gallery

References

External links