View source for Citron

{{short description|Species of citrus plant}}
{{Other uses}}
{{distinguish|Citroën}}
{{Use dmy dates|date=November 2025}}
{{Speciesbox
|image = Chinesische Zedrat Zitrone.jpg
|status = LC
|status_system = IUCN3.1
|status_ref = <ref>Plummer, J. 2021. Citrus medica. The IUCN Red List of Threatened Species 2021: e.T62041221A62041228. Downloaded on 6 September 2021.</ref>
|genus = Citrus
|species = medica
|authority = [[Carl Linnaeus|L.]]
|synonyms = <!-- Too many to list -->
* ''Citrus alata'' <small>([[Chōzaburō Tanaka|Tanaka]]) Tanaka</small>
* ''Citrus bicolor'' <small>[[Pierre Antoine Poiteau|Poit.]] & [[Pierre Jean François Turpin|Turpin]]</small>
* ''Citrus cedra'' <small>Link</small> 
* ''Citrus fragrans'' <small>[[Richard Anthony Salisbury|Salisb.]]</small>
* ''Citrus limonimedica'' <small>([[Alfred Wyndham Lushington|Lush.]])</small>
* ''Citrus odorata'' <small>(Wester) Tanaka</small>
|synonyms_ref = <ref>{{cite book |chapter=''Citrus'' taxonomy |last1=Ollitrault |first1=Patrick |last2=Curk |first2=Franck |last3=Krueger |first3=Robert |title=The Citrus Genus |editor-last1=Talon |editor-first1=Manuel |editor-last2=Caruso |editor-first2=Marco |editor-last3=Gmitter |editor-first3=Fred G Jr. |publisher=Elsevier |year=2020 |pages=57–81 |isbn=9780128121634 |chapter-url=https://books.google.com/books?id=2wo4swEACAAJ&pg=PA57 |doi=10.1016/B978-0-12-812163-4.00004-8 |s2cid=242819146 }}</ref><ref name="WFO">{{cite web |url=http://www.worldfloraonline.org/taxon/wfo-0000608140#synonyms |title=''Citrus medica'' L. Sp. Pl. : 782 (1753) |date=2022 |website=World Flora Online |publisher=World Flora Consortium |access-date=11 December 2022 |archive-date=11 December 2022 |archive-url=https://web.archive.org/web/20221211131721/http://www.worldfloraonline.org/taxon/wfo-0000608140#synonyms |url-status=live }}</ref>
}}

The '''citron''' ('''''Citrus medica''''') <ref>{{cite web |title=Cedrate |url=https://www.collinsdictionary.com/dictionary/english/cedrate |website=Collins English Dictionary |access-date=2 October 2022 |archive-date=30 April 2021 |archive-url=https://web.archive.org/web/20210430124554/https://www.collinsdictionary.com/dictionary/english/cedrate |url-status=live }}</ref> is a large fragrant [[citrus]] fruit with a thick, coarse  [[Peel (fruit)|rind]]. It resembles a [[lemon]], but is larger.<ref>{{Cite book |last=Davidson |first=Alan |author-link=Alan Davidson (food writer) |title-link=The Oxford Companion to Food |title=The Oxford Companion to Food |date=2014 |editor=Tom Jaine |others=Illustrated by Soun Vannithone |isbn=978-0-19-967733-7 |edition=3rd |publisher=Oxford University Press |oclc=890807357 |page=191 }}</ref> It is one of the [[Citrus taxonomy#Citrons|original citrus fruits]] from which all other citrus types developed through natural [[hybrid speciation]] or artificial [[Hybrid (biology)|hybridization]].<ref>{{cite book |author=Klein, J. |date=2014 |title=Medicinal and Aromatic Plants of the Middle-East |chapter=Citron Cultivation, Production and Uses in the Mediterranean Region |publisher=Springer Netherlands |editor1=Z. Yaniv |editor2=N. Dudai |pages=199–214 |volume=2 |doi=10.1007/978-94-017-9276-9_10 |series=Medicinal and Aromatic Plants of the World |isbn=978-94-017-9275-2 }}</ref> Though citron cultivars take on a wide variety of physical forms, they are all closely related genetically. It is used in Asian and Mediterranean cuisine, traditional medicines, perfume, and religious rituals and offerings. Hybrids of citrons with other citrus are commercially more prominent, notably lemons and many [[Lime (fruit)|limes]].

== Etymology ==
The fruit's name is derived from the Latin ''citrus'', which is also the origin of the genus name. The binomial name ''Citrus medica'' derives from [[Median kingdom|Media]], the kingdom of the Medes, where it was believed to originate (but see "Origin and distribution" below).<ref name=":0">{{Cite book |last=Attlee |first=Helena |title=The land where lemons grow: the story of Italy and its citrus fruit |date=2015 |publisher=Penguin Books |isbn=978-0-241-95257-3 |location=London |pages=201 }}</ref>

=== Other languages ===
A source of confusion is that ''[[:wikt:citron|<nowiki/>'citron]]''<nowiki/>' in French and English are [[false friend]]s, as the French word ''<nowiki/>'citron'<nowiki/>'' refers to what in English is a lemon; whereas the French word for the citron is ''<nowiki/>'cédrat'''. Into the 16th century, the English term ''citron'' included the lemon and perhaps the lime as well.<ref>{{cite web |url=http://www.oed.com/ |title=Home : Oxford English Dictionary |publisher=oed.com |access-date=19 May 2012 |archive-date=11 January 2008 |archive-url=https://web.archive.org/web/20080111125659/http://www.oed.com/ |url-status=live }}</ref>{{failed verification|date=December 2024|reason=link to home page instead of entry. Cannot find similar statement on other online dictionaries.}} Other languages that use variants of ''citron'' to refer to the lemon include Armenian, Czech, Dutch, Finnish, German, Estonian, Latvian, Lithuanian, Hungarian, Esperanto, Polish and the Scandinavian languages.<ref>{{Cite web |title="Lemon" in European languages |url=https://jakubmarian.com/lemon-in-european-languages/ |access-date=20 August 2025 |language=en |archive-date=15 July 2024 |archive-url=https://web.archive.org/web/20240715012357/https://jakubmarian.com/lemon-in-european-languages/ |url-status=live }}</ref>

In Italian it is known as {{lang|it|cedro}}, the same name used also to indicate the coniferous tree [[cedrus|cedar]]. Similarly, in Latin, citrus, or [[thyine wood]] referred to the wood of a North African cypress, ''[[Tetraclinis articulata]]''.
In [[Indo-Iranian languages]], it is called {{Transliteration|fa|toranj}}, as against {{Transliteration|fa|naranj}} ('bitter orange'). Both names were borrowed into [[Arabic]] and introduced into Spain and Portugal after their occupation by [[Muslims]] in AD 711, whence the latter became the source of the name ''orange'' through [[rebracketing]] (and the former of 'toronja' and 'toranja', which today describe the [[grapefruit]] in Spanish and Portuguese respectively).<ref>{{cite web |url=http://www.plantlives.com/docs/C/Citrus_medica.pdf |title=''Citrus medica'' |date=2 October 2021 |publisher=plantlives.com |archive-date=21 April 2021 |archive-url=https://web.archive.org/web/20210421102229/http://www.plantlives.com/docs/C/Citrus_medica.pdf |url-status=usurped }}</ref>

Dutch merchants seasonally import {{langr|id|Sukade}} for baked goods; a thick, light green colored commercially candied half peeling from Indonesia and other countries ({{lang|id|sukade}} – Indonesian word for love, ''Citrus médica'' variety 'Macrocárpa'), which can reach 2.5 kilograms mass. A bitter taste is removed by salt treatment before processing into confectionery.<ref>{{cite book |last1=Hvass |first1=Else |title=Nuttige Planten In Kleur |date=1965 |publisher=Mousault |location=Amsterdam |isbn=9789022610220 |pages=76, 161 |edition=nedersland |url=https://www.deslegte.com/nuttige-planten-in-kleur-118498/ |archive-date=11 January 2022 |access-date=11 January 2022 |archive-url=https://web.archive.org/web/20220111091837/https://www.deslegte.com/nuttige-planten-in-kleur-118498/ |url-status=live }}</ref>

In Hebrew it is called an ''[[Etrog]]'' ({{lang|he|אתרוג}}); in Yiddish, it is pronounced ''"esrog"'' or "''esreg''". The citron plays an important role in the harvest holiday of [[Sukkot]] paired with ''[[lulav]]im'' (fronds of the [[date palm]]).

== Origin and distribution ==
[[File:Map of inferred original wild ranges of the main Citrus cultivars, and selected relevant wild taxa (Fuller et al., 2017).png|thumb|Map of inferred original wild ranges of the main ''Citrus'' cultivars, and selected relevant wild taxa<ref name="fuller">{{cite book |first1=Dorian Q. |last1=Fuller |first2=Cristina |last2=Castillo |first3=Eleanor |last3=Kingwell-Banham |first4=Ling |last4=Qin |first5=Alison |last5=Weisskopf |editor1-first=Véronique |editor1-last=Zech-Matterne |editor2-first=Girolamo |editor2-last=Fiorentino |title=AGRUMED: Archaeology and history of citrus fruit in the Mediterranean |chapter=Charred pomelo peel, historical linguistics and other tree crops: approaches to framing the historical context of early ''Citrus'' cultivation in East, South and Southeast Asia |publisher=Publications du Centre Jean Bérard |year=2017 |pages=29–48 |isbn=9782918887775 |doi=10.4000/books.pcjb.2107 |hdl=11573/1077421 |url=https://hal.archives-ouvertes.fr/hal-03501166/file/2017-Ruas-etal-Citrus.pdf |chapter-url=https://books.openedition.org/pcjb/2173?lang=en |archive-date=21 August 2022 |access-date=6 January 2023 |archive-url=https://web.archive.org/web/20220821061319/https://hal.archives-ouvertes.fr/hal-03501166/file/2017-Ruas-etal-Citrus.pdf |url-status=live }}</ref>]]
The citron is an old and original citrus species.<ref name=Chambers>{{cite book |last=Chambers |first=William and Robert |title=Chambers's Encyclopedia: A Dictionary of Universal Knowledge for the People |year=1862 |publisher=W. and R. Chambers |location=London |page=55, vol. 3 |url=https://books.google.com/books?id=8gTj2h8cFM4C&dq=oil+of+cedrate&pg=PA55 }}</ref>

There is molecular evidence that most cultivated citrus species arose by [[Hybrid (biology)#Hybrid plants|hybridization]] of a small number of ancestral types: the citron, [[pomelo]], [[Mandarin orange|mandarin]] and, to a lesser extent, [[Papeda (citrus)|papedas]] and [[kumquat]]. The citron is usually [[fertilized]] by [[self-pollination]], which results in their displaying a high degree of genetic [[zygosity|homozygosity]]. It is the male parent of any citrus hybrid rather than a female one.<ref name="HortScience 2005" /><ref>{{cite journal |author=E. Nicolosi |author2=Z. N. Deng |author3=A. Gentile |author4=S. La Malfa |author5=G. Continella |author6=E. Tribulato |title=Citrus phylogeny and genetic origin of important species as investigated by molecular markers |journal=Theoretical and Applied Genetics |date=June 2000 |volume=100 |issue=8 |pages=1155–1166 |doi=10.1007/s001220051419 |s2cid=24057066 }}</ref><ref>{{cite journal |author=Noelle A. Barkley |author2=Mikeal L. Roose |author3=Robert R. Krueger |author4=Claire T. Federici |title=Assessing genetic diversity and population structure in a ''Citrus'' germplasm collection utilizing simple sequence repeat markers (SSRs) |journal=Theoretical and Applied Genetics |date=May 2006 |volume=112 |issue=8 |pages=1519–1531 |doi=10.1007/s00122-006-0255-9 |pmid=16699791 |s2cid=7667126 |url=https://naldc-legacy.nal.usda.gov/naldc/download.xhtml?id=11065&content=PDF |access-date=4 December 2018 |archive-date=9 March 2021 |archive-url=https://web.archive.org/web/20210309064039/https://naldc-legacy.nal.usda.gov/naldc/download.xhtml?id=11065&content=PDF |url-status=dead |url-access=subscription }}</ref><ref>{{cite journal |author=Asad Asadi Abkenar |author2=Shiro Isshiki |author3=Yosuke Tashiro |title=Phylogenetic relationships in the 'true citrus fruit trees' revealed by PCR-RFLP analysis of cpDNA |journal=Scientia Horticulturae |volume=102 |issue=2 |date=1 November 2004 |pages=233–242 |doi=10.1016/j.scienta.2004.01.003 |bibcode=2004ScHor.102..233A }}</ref><ref>{{cite journal |author=C. A. Krug |title=Chromosome Numbers in the Subfamily Aurantioideae with Special Reference to the Genus ''Citrus'' |journal=Botanical Gazette |volume=104 |number=4 |date=June 1943 |pages=602–611 |jstor=2472147 |doi=10.1086/335173 |s2cid=84015769 }}</ref><ref>{{cite journal |author=R. Carvalho |author2=W. S. Soares Filho |author3=A. C. Brasileiro-Vidal |author4=M. Guerra |title=The relationships among lemons, limes and citron: a chromosomal comparison |journal=Cytogenetic and Genome Research |volume=109 |issue=1–3 |date=March 2005 |doi=10.1159/000082410 |pages=276–282 |pmid=15753587 |s2cid=26046238 }}</ref><ref name="Talon">{{cite journal |title=Genomics of the origin and evolution of ''Citrus'' |last1=Wu |first1=Guohong Albert |last2=Terol |first2=Javier |last3=Ibanez |first3=Victoria |last4=López-García |first4=Antonio |last5=Pérez-Román |first5=Estela |last6=Borredá |first6=Carles |last7=Domingo |first7=Concha |last8=Tadeo |first8=Francisco R |last9=Carbonell-Caballero |first9=Jose | last10=Alonso | first10=Roberto |last11=Curk |first11=Franck |last12=Du |first12=Dongliang |last13=Ollitrault |first13=Patrick |last14=Roose |first14=Mikeal L. Roose |last15=Dopazo |first15=Joaquin |last16=Gmitter Jr |first16=Frederick G. |last17=Rokhsar |first17=Daniel |last18=Talon |first18=Manuel |journal=Nature |year=2018 |volume=554 |issue=7692 |pages=311–316 |doi=10.1038/nature25447 |pmid=29414943 |bibcode=2018Natur.554..311W |doi-access=free |hdl=20.500.11939/5741 |hdl-access=free }}</ref>

Archaeological evidence for citrus fruits has been limited, as neither seeds nor pollen are likely to be routinely recovered in archaeology.<ref>{{cite book |last1=Fuller |first1=Dorian Q. |last2=Castillo |first2=Cristina |last3=Kingwell-Banham |first3=Eleanor |last4=Qin |first4=Ling |last5=Weisskopf |first5=Alison |chapter=Charred pummelo peel, historical linguistics and other tree crops: Approaches to framing the historical context of early ''Citrus'' cultivation in East, South and Southeast Asia |chapter-url=https://books.openedition.org/pcjb/2173?lang=en#ftn2 |title=AGRUMED: Archaeology and history of citrus fruit in the Mediterranean : Acclimatization, diversifications, uses |publisher=Publications du Centre Jean Bérard |language=en |date=15 January 2018 |isbn=9782918887775 |archive-date=28 September 2020 |access-date=6 October 2020 |archive-url=https://web.archive.org/web/20200928014252/https://books.openedition.org/pcjb/2173?lang=en#ftn2 |url-status=live }}</ref> The citron is thought to have been native to the southeast foothills of the [[Himalayas]].<ref name="Talon" /> Despite its scientific designation, which is an adaptation of the old name in classical Greek sources “Median pome”, this fruit was not indigenous to Media or ancient Media;<ref>{{cite web |last1=Foundation |first1=Encyclopaedia Iranica |url=https://www.iranicaonline.org/articles/citrus-fruits- |title=Welcome to Encyclopaedia Iranica |access-date=19 March 2024 |archive-date=30 April 2024 |archive-url=https://web.archive.org/web/20240430053629/https://www.iranicaonline.org/articles/citrus-fruits- |url-status=live }}</ref><ref>''Inquiry into Plants'' 4.iv.2.</ref> it was mostly cultivated on shores of the [[Caspian Sea]] (north of Mazandarn and Gilan) on its way to the [[Mediterranean basin]], where it was cultivated during the later centuries in different areas as described by Erich Isaac.<ref>{{cite journal |author=Erich Isaac |title=The Citron in the Mediterranean: a study in religious influences |journal=Economic Geography |volume=35 |issue=1 |date=January 1959 |pages=71–78 |doi=10.2307/142080 |jstor=142080 }}</ref> Many mention the role of [[Alexander the Great]] and his armies as they attacked [[Achaemenid Empire|Iran]] and what is today Pakistan, as being responsible for the spread of the citron westward, reaching the European countries such as Greece and Italy.<ref name="Purdue Citron" /><ref name="Simoons p.200">{{cite book |author=Frederick J. Simoons |title=Food in China: a cultural and historical inquiry |publisher=CRC Press |year=1990 |isbn=9780849388040 |url=https://books.google.com/books?id=Fo087ZxohA4C&q=alexander+the+great+citron&pg=PA200 |page=200 }}</ref><ref>{{cite web |url=http://www.citrusvariety.ucr.edu/citrus/ethrog.html |title=ethrog |publisher=University of California, Riverside |access-date=4 May 2008 |archive-date=8 June 2015 |archive-url=https://web.archive.org/web/20150608215246/http://www.citrusvariety.ucr.edu/citrus/ethrog.html |url-status=dead }}</ref><ref>{{cite book |author=Marion Eugene Ensminger |author2=Audrey H. Ensminger |url=https://books.google.com/books?id=o3UD2iL4sAAC&q=Alexander+the+great+citron&pg=PA424 |title=Foods & Nutrition Encyclopedia |edition=2nd |volume=1 |publisher=CRC Press |year=1993 |isbn=9780849389818 |page=424 }}</ref><ref>{{cite book |author=Francesco Calabrese |chapter=Origin and history |editor=Giovanni Dugo |editor2=Angelo Di Giacomo |chapter-url=https://books.google.com/books?id=OLaykfpqSaYC&q=alexander+the+great+citron&pg=PA4 |title=''Citrus'': The Citrus Genus |publisher=CRC Press |date=2003 |page=4 |isbn=9780203216613 }}</ref><ref>[https://books.google.com/books?id=SmRJnd73dbYC&dq=alexander+the+great+citron&pg=PA7 Biology of Citrus]{{dead link|date=November 2016 }}</ref><ref>{{cite book |author=H. Harold Hume |url=https://books.google.com/books?id=WP3ohzxbRxgC&q=alexander+the+great+citron&pg=PA59 |title=Citrus Fruits and Their Culture |publisher=Read Books |year=2007 |isbn=9781406781564 |page=59 }}</ref><ref>{{cite book |author=Emmanuel Bonavia |author-link=Emmanuel Bonavia |url=https://books.google.com/books?id=tsNBAAAAIAAJ&q=alexander%20the%20great%20citron&pg=PA255 |title=The Cultivated Oranges and Lemons, Etc. of India and Ceylon |publisher=W. H. Allen |year=1888 |page=255 }}</ref>

=== Antiquity ===
{{See also|Etrog#Historic cultivation areas}}
Leviticus mentions the "fruit of the beautiful ('hadar') tree" as being required for ritual use during the [[Feast of Tabernacles]] ([http://www.mechon-mamre.org/p/pt/pt0323.htm Lev. 23:40]). According to Jewish Rabbinical tradition, the "fruit of the tree hadar" refers to the citron. [[Sukkah (Talmud)|Mishna Sukkah]], {{Circa|2nd century AD}}, deals with [[halakhic]] aspects of the citron.

[[file: Segment_of_synagogue_mosaic_floor_from_Tiberias_at_Eretz_Israel_Museum_in_Tel_Aviv.jpg|thumb|upright|Ancient mosaic of Tiberian Synagogue depicting citrons]]

The [[Egyptologist]] and [[archaeologist]] [[Victor Loret]] said he had identified it depicted on the walls of the [[Botanical garden of Thutmosis III|botanical garden]] at the [[Karnak Temple]], which dates back to the time of [[Thutmosis III]], approximately 3,500 years ago.<ref>{{cite journal |title=Scientific Committee, March 28, 1893: The Antiquity of the Citron in Egypt |url=https://books.google.com/books?id=21oCAAAAYAAJ&q=citron+persian+gulf&pg=RA3-PR20 |journal=Journal of the Royal Horticultural Society |volume=16 |last1=Britain) |first1=Royal Horticultural Society (Great |year=1894 }}</ref> Citron was also cultivated in [[Sumer]] as early as the 3rd millennium BC.

The citron has been cultivated since ancient times, predating the cultivation of other ''Citrus'' [[species]].<ref>{{cite journal |last=Ramón-Laca |first=L. |title=The Introduction of Cultivated Citrus to Europe via northern Africa and the Iberian Peninsula |journal=Economic Botany |date=Winter 2003 |volume=57 |issue=4 |pages=502–514 |doi=10.1663/0013-0001(2003)057[0502:tiocct]2.0.co;2 |s2cid=33447866 |doi-access=free }}</ref>

=== Theophrastus ===
The following description on citron was given by [[Theophrastus]]<ref>''Historia plantarum'' 4.4.2–3 (''exc.'' Athenaeus ''Deipnosophistae'' 3.83.d-f); cf. Vergil ''Georgics'' 2.126-135; Pliny ''Naturalis historia'' 12.15,16.</ref>
[[File:A species of citrus fruit (Citrus sarcodactylis Hort. Bog.); Wellcome V0042687.jpg|thumb|Illustration of [[fingered citron]] with the leaves and thorns that are common to all varieties of citron]]
<blockquote>In the east and south there are special plants ... i.e. in Media and Persia there are many types of fruit, between them there is a fruit called Median or Persian Apple. The tree has a leaf similar to and almost identical with that of the ''andrachn'' (''[[Arbutus andrachne]]'' L.), but has [[Thorns, spines, and prickles|thorns]] like those of the ''[[apios]]'' (the wild pear, ''Pyrus amygdaliformis'' Vill.) or the [[firethorn]] (''Cotoneaster pyracantha'' Spach.), except that they are white, smooth, sharp and strong. The fruit is not eaten, but is very fragrant, as is also the [[leaf]] of the tree; and the fruit is put among [[clothes]], it keeps them from being [[moth]]-eaten. It is also useful when one has drunk deadly poison, for when it is administered in wine; it upsets the [[stomach]] and brings up the poison. It is also useful to improve the [[breath]], for if one boils the inner part of the fruit in a dish or squeezes it into the mouth in some other medium, it makes the breath more pleasant.

The seed is removed from the fruit and sown in the spring in carefully tilled beds, and it is watered every fourth or fifth day. As soon the plant is strong it is [[Transplanting|transplanted]], also in the spring, to a soft, well watered site, where the soil is not very fine, for it prefers such places.

And it bears its fruit at all seasons, for when some have gathered, the flower of the others is on the tree and is ripening others. Of the [[flower]]s I have said<ref>''Historia plantarum'' 1.13.4.</ref> those that have a sort of distaff [meaning the [[carpel|pistil]]] projecting from the middle are fertile, while those that do not have this are sterile. It is also sown, like [[date palm]]s, in pots punctured with holes.

This tree, as has been remarked, grows in Media and Persia.</blockquote>

=== Pliny the Elder ===
Citron was also described by [[Pliny the Elder]], who called it ''nata Assyria malus''. The following is from his book ''[[Natural History (Pliny)|Natural History]]'':
<blockquote>There is another tree also with the same name of "citrus", and bears a fruit that is held by some persons in particular dislike for its smell and remarkable bitterness; while, on the other hand, there are some who esteem it very highly. This tree is used as an ornament to houses; it requires, however, no further description.<ref>{{cite web |title=Chap. 31.—The Citron-Tree |work=Perseus Digital Library |publisher=Tufts University |url=https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.02.0137%3Abook%3D13%3Achapter%3D31 |access-date=20 February 2021 |archive-date=26 January 2021 |archive-url=https://web.archive.org/web/20210126195642/http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.02.0137%3Abook%3D13%3Achapter%3D31 |url-status=live }} excerpting from {{cite book |title=The Natural History. Pliny the Elder. |editor1=John Bostock |editor2=H. T. Riley |location=London |publisher=Taylor and Francis |year=1855 }}</ref>

The citron tree, called the Assyrian, and by some the Median or Persian apple, is an antidote against poisons. The leaf is similar to that of the [[Arbutus|arbute]], except that it has small prickles running across it. As to the fruit, it is never eaten, but it is remarkable for its extremely powerful smell, which is the case, also, with the leaves; indeed, the odour is so strong, that it will penetrate clothes, when they are once impregnated with it, and hence it is very useful in repelling the attacks of noxious insects.

The tree bears fruit at all seasons of the year; while some is falling off, other fruit is ripening, and other, again, just bursting into birth. Various nations have attempted to naturalize this tree among them, for the sake of its medica or Persian properties, by planting it in pots of clay, with holes drilled in them, for the purpose of introducing the air to the roots; and I would here remark, once for all, that it is as well to remember that the best plan is to pack all slips of trees that have to be carried to any distance, as close together as they can possibly be placed.

It has been found, however, that this tree will grow nowhere except in Persia. It is this fruit, the pips of which, as we have already mentioned, the [[Parthia]]n grandees employ in seasoning their [[ragout]]s, as being peculiarly conducive to the sweetening of the breath. We find no other tree very highly commended that is produced in Media.<ref>{{cite web |url=https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.02.0137%3Abook%3D12%3Achapter%3D7 |title=Pliny the Elder, The Natural History, Book XII. The Natural History of Trees, Chap. 7. (3.)—How the Citron Is Planted. |publisher=Tufts University |access-date=20 February 2021 |archive-date=25 September 2020 |archive-url=https://web.archive.org/web/20200925023827/http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.02.0137%3Abook%3D12%3Achapter%3D7 |url-status=live }}</ref>

Citrons, either the pulp of them or the pips, are taken in wine as an antidote to poisons. A decoction of citrons, or the juice extracted from them, is used as a gargle to impart sweetness to the breath. The pips of this fruit are recommended for pregnant women to chew when affected with [[qualmishness]]. Citrons are good, also, for a weak stomach, but it is not easy to eat them except with vinegar.<ref>{{cite web |url=https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.02.0137%3Abook%3D23%3Achapter%3D56 |title=Pliny the Elder, The Natural History, Book XXIII. The Remedies Derived from the Cultivated Trees., Chap. 56.—Citrons: Five Observations upon Them. |publisher=Tufts University |access-date=20 February 2021 |archive-date=27 July 2021 |archive-url=https://web.archive.org/web/20210727034110/https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.02.0137%3Abook%3D23%3Achapter%3D56 |url-status=live }}</ref></blockquote>

=== Medieval authors ===
[[Ibn al-'Awwam]]'s 12th-century agricultural encyclopedia, ''Book on Agriculture'', contains an article on citron tree cultivation in Spain.<ref>{{cite book |last=Ibn al-'Awwam |first=Yaḥyá |author-link=Ibn al-'Awwam |title=Le livre de l'agriculture d'Ibn-al-Awam (kitab-al-felahah) |year=1864 |location=Paris |publisher=A. Franck |translator=J.-J. Clement-Mullet |pages=292–297 (ch. 7 - Article 29) |url=https://archive.org/details/lelivredelagric00algoog/page/n14/mode/2up |language=fr |oclc=780050566}} (pp. [https://archive.org/details/lelivredelagric00algoog/page/n400/mode/2up 292]–297 (Article XXIX)</ref>

== Description and variation ==
[[File:Zitronatszitrone.jpg|thumb|A citron or [[citrus hybrid|citron-like hybrid]] of Italian origin, showing the thick rind]]

=== Fruit ===
The citron fruit is usually [[Glossary of leaf morphology#ovate|ovate]] or oblong, narrowing towards the [[Etrog#Pitom|stylar]] end. However, the citron's fruit shape is highly variable, due to the large quantity of [[Mesocarp#Mesocarp|albedo]], which forms independently according to the fruits' position on the tree, twig orientation, and many other factors. The rind is leathery, furrowed, and adherent. The inner portion is thick, white and hard; the outer is uniformly thin and very fragrant. The pulp is usually acidic, but also can be sweet, and some varieties are entirely pulpless.

Most citron varieties contain a large number of [[monoembryonic]] seeds. The seeds are white with dark inner coats and red-purplish [[chalazal spot]]s for the acidic varieties, and colorless for the sweet ones. Some citron varieties have persistent [[carpel|styles]] which do not fall off after fecundation. Those are usually preferred for ritual ''[[etrog]]'' use in Judaism.

Some citrons have medium-sized oil bubbles at the outer surface, medially distant to each other. Some varieties are ribbed and faintly warted on the outer surface. A fingered citron variety is commonly called [[Buddha's hand]].

The color varies from green, when unripe, to a yellow-orange when overripe. The citron does not fall off the tree and can reach 8–10 pounds (4–5&nbsp;kg) if not picked before fully mature.<ref>''Un curieux Cedrat marocain'', Chapot 1950.</ref><ref name="HortScience 2005">{{Cite web |url=https://ods.od.nih.gov/Research/PubMed_Dietary_Supplement_Subset.aspx?mode2=detail&origin=ibids_references&therow=796030 |title=The Search for the Authentic Citron: Historic and Genetic Analysis; ''HortScience'' '''40'''(7):1963–1968. 2005 |access-date=28 June 2025 |archive-date=10 August 2011 |archive-url=https://web.archive.org/web/20110810164631/http://ods.od.nih.gov/Research/PubMed_Dietary_Supplement_Subset.aspx?mode2=detail&origin=ibids_references&therow=796030 |url-status=live }}</ref> However, they should be picked before the winter, as the branches might bend or break to the ground, and may cause numerous fungal diseases for the tree.

Despite the wide variety of forms taken on by the fruit, citrons are all closely related genetically, representing a single species.<ref name="Talon" /><ref name="Ramadugu">{{cite journal |last1=Ramadugu |first1=Chandrika |last2=Keremane |first2=Manjunath L |last3=Hu |first3=Xulan |last4=Karp |first4=David |last5=Frederici |first5=Claire T |last6=Kahn |first6=Tracy |last7=Roose |first7=Mikeal L |last8=Lee |first8=Richard F. |title=Genetic analysis of citron (''Citrus medica'' L.) using simple sequence repeats and single nucleotide polymorphisms |journal=Scientia Horticulturae |volume=195 |pages=124–137 |year=2015 |doi=10.1016/j.scienta.2015.09.004 |doi-access=free |bibcode=2015ScHor.195..124R }}</ref> Genetic analysis divides the known cultivars into three clusters: a Mediterranean cluster thought to have originated in India, and two clusters predominantly found in China, one representing the fingered citrons, and another consisting of non-fingered varieties.<ref name="Ramadugu" />

=== Plant ===
[[File:Citron Balady Etrog Simanim.jpg|thumb|A pure citron of any kind has a large portion of [[Fruit anatomy#Mesocarp|albedo]], which is important for the production of [[succade]].]]

''Citrus medica'' is a slow-growing [[shrub]] or small tree that reaches a height of about {{convert|8|to|15|ft|m|round=0.5|order=flip|abbr=off}}. It has irregular straggling branches and stiff twigs and long [[spine (botany)|spines]] at the [[leaf]] [[axil]]s. The evergreen leaves are green and lemon-scented with slightly serrate edges, ovate-lanceolate or ovate elliptic {{convert|2+1/2|to(-)|7|in|mm|-1|order=flip}} long. [[Petiole (botany)|Petioles]] are usually wingless or with minor wings. The clustered flowers of the acidic varieties are purplish tinted from outside, but the sweet ones are white-yellowish.
{{Citron varieties}}

The citron tree is very vigorous with almost no dormancy, blooming several times a year, and is therefore fragile and extremely sensitive to frost.<ref>{{cite web |url=http://lib.ucr.edu/agnic/webber/Vol1/Chapter4.html#acid |title=Website Disabled |publisher=University of California, Riverside |url-status=dead |archive-url=https://web.archive.org/web/20080308005736/http://lib.ucr.edu/agnic/webber/Vol1/Chapter4.html#acid |archive-date=8 March 2008 }}</ref>

=== Varieties and hybrids ===
The [[acid]]ic varieties include the [[Florentine citron|Florentine]] and [[Diamante citron]] from Italy, the [[Greek citron]] and the [[Balady citron]] from Israel.<ref>{{cite journal |url=https://www.researchgate.net/publication/234002705 |title=A review on citron-pharmacognosy, phytochemistry and medicinal uses |author1=Meena, Ajay Kumar |author2=Kandale, Ajit |author3=Rao, M. M. |author4=Panda, P. |author5=Reddy, Govind |journal=The Journal of Pharmacy |volume=2 |issue=1 |pages=14–20 |year=2011 }}</ref> The sweet varieties include the [[Corsican citron|Corsican]] and [[Moroccan citron]]s. The pulpless varieties also include some [[Fingered citron|fingered]] varieties and the [[Yemenite citron]].

There are also a number of citron [[hybrid (biology)|hybrids]]; for example, [[ponderosa lemon]], the [[lumia (citrus)|lumia]] and [[rhobs el Arsa]] are known citron hybrids. Some claim<ref>{{Cite web |title=ponderosa |url=https://citrusvariety.ucr.edu/citrus/ponderosa.html |access-date=6 June 2022 |website=citrusvariety.ucr.edu |archive-date=3 March 2021 |archive-url=https://web.archive.org/web/20210303043405/https://citrusvariety.ucr.edu/citrus/ponderosa.html |url-status=live }}</ref> that even the [[Florentine citron]] is not pure citron, but a citron hybrid.

== Uses ==
=== Culinary ===
{{Main|Succade}}

While the lemon and [[Orange (fruit)|orange]] are primarily peeled to consume their pulpy and [[juice|juicy]] [[flavedo|segments]], the citron's pulp is dry, containing a small quantity of juice, if any. The main content of a citron fruit is its thick white rind, which adheres to the segments and cannot easily be separated from them. The citron gets halved and depulped, then its rind (the thicker the better) is cut into pieces. Those are cooked in sugar syrup and used as a [[spoon sweet]] known in Greek as "kítro glykó" (κίτρο γλυκό), or diced and candied with sugar and used as a confection in cakes. In Italy, a soft drink called "Cedrata" is made from the fruit<ref>{{Cite web |last=Parla |first=Katie |date=10 May 2009 |title=Cedrata, A Strange and Refreshing Beverage |url=https://katieparla.com/cedrata-a-strange-and-refreshing-beverage/ |access-date=20 August 2025 |website=Katie Parla |language=en-US |archive-date=22 April 2024 |archive-url=https://web.archive.org/web/20240422040730/https://katieparla.com/cedrata-a-strange-and-refreshing-beverage/ |url-status=live }}</ref> as well as a dense and powerful citron liqueur called “cedro” or “cedrello”.<ref name=":0" />

In Samoa a refreshing drink called "vai tipolo" is made from squeezed juice. It is also added to a raw fish dish called "oka" and to a variation of palusami or luáu.

Citron is a regularly used item in Asian cuisine.

Today the citron is also used for the [[fragrance]] or [[Zest (ingredient)|zest]] of its [[flavedo]], but the most important part is still the inner rind (known as [[pith]] or ''[[Fruit anatomy#Mesocarp|albedo]]''), which is a fairly important article in [[international trade]] and is widely employed in the food industry as [[succade]],<ref name="Purdue Citron">{{cite web |url=http://www.hort.purdue.edu/newcrop/morton/citron.html |title=Citron: ''Citrus medica'' Linn. |publisher=Purdue University |access-date=20 August 2007 |archive-date=20 March 2022 |archive-url=https://web.archive.org/web/20220320081540/https://hort.purdue.edu/newcrop/morton/citron.html |url-status=live }}</ref> as it is known when it is candied in sugar.

The dozens of varieties of citron are collectively known as ''Lebu'' in [[Bengali cuisine|Bangladesh, West Bengal]], where it is the primary citrus fruit.

In Iran the citron's thick white rind is used to make jam; in Pakistan the fruit is used to make jam but is also pickled; in [[South Indian cuisine]], some varieties of citron (collectively referred to as "Narthangai" in [[Tamil language|Tamil]] and "Heralikayi" in [[Kannada]]) are widely used in pickles and preserves. In [[Karnataka]], heralikayi (citron) is used to make lemon rice. In [[Kutch]], Gujarat, it is used to make pickle, wherein entire slices of fruits are salted, dried and mixed with [[jaggery]] and spices to make sweet spicy pickle.<ref>{{cite web |title=Bijora Pickle |url=http://www.jainworld.com/jainfoodrecipes/pic_bijora.asp |publisher=Jain World |access-date=23 August 2016 |archive-url=https://web.archive.org/web/20161220073239/http://www.jainworld.com/jainfoodrecipes/pic_bijora.asp |archive-date=20 December 2016 |url-status=dead }}</ref> In the United States, citron is an important ingredient in holiday [[fruitcakes]].

<gallery widths="200px" heights="160px">
File:Halv sukat.JPG|A citron halved and depulped, cooked in sugar
File:Bicchiere di tassoni1.jpg|''Cedrata'', a citron soft drink from Italy
File:Citron cake.jpg|Citron torte
</gallery>

===Medicine ===
From [[ancient]] through [[medieval]] times, the citron was used mainly for [[traditional medicine|supposed medical purposes]] to combat [[seasickness]], [[scurvy]] and other disorders. Pietro Andrea [[Pietro Andrea Mattioli|Mattioli]]'s ''Commentaries'' (1544) recommended using the essential oil of citrons to preserve dead bodies and suggested using it as a contraceptive.<ref name=":0" /> 

Citron and its bioactive [[Phytochemical|phytochemicals]] have demonstrated activity against various pathogenic microorganisms.<ref>{{Cite journal |last1=Dahan |first1=Arik |last2=Yarmolinsky |first2=Ludmila |last3=Nakonechny |first3=Faina |last4=Semenova |first4=Olga |last5=Khalfin |first5=Boris |last6=Ben-Shabat |first6=Shimon |date=9 June 2025 |title=Etrog Citron (''Citrus medica'') as a Novel Source of Antimicrobial Agents: Overview of Its Bioactive Phytochemicals and Delivery Approaches |journal=Pharmaceutics |language=en |volume=17 |issue=6 |pages=761 |doi=10.3390/pharmaceutics17060761 |doi-access=free |issn=1999-4923 |pmc=12196015 |pmid=40574073 }}</ref> The juice of the citron has a high content of [[vitamin C]] and [[dietary fiber]] ([[pectin]]) which can be extracted from the thick [[flavedo|albedo]] of the citron.<ref>{{cite journal |author=Frederick Hardy |title=The Extraction of Pectin from the Fruit Rind of the Lime (''Citrus medica acida'') |journal=Biochemical Journal |volume=18 |issue=2 |year=1924 |pages=283–290 |pmc=1259415 |pmid=16743304 |doi=10.1042/bj0180283}}
</ref>

=== Religious ===
==== In Judaism ====
{{Main|Etrog}}
The citron (the word for which in Hebrew is ''[[etrog]]'') is used by Jews for a religious [[ritual]] during the Jewish harvest holiday of [[Sukkot]], the [[Feast of Tabernacles]]; therefore, it is considered to be a Jewish symbol, one found on various Hebrew antiques and archaeological findings.<ref>See [[Etrog]]</ref>

==== In Buddhism ====
{{Main|Buddha's hand}}
A variety of citron native to China has sections that separate into finger-like parts and is used as an [[offering (Buddhism)|offering]] in [[Buddhist]] temples.<ref>{{Cite web |title=buddha |url=https://citrusvariety.ucr.edu/citrus/buddha.html |access-date=6 June 2022 |website=citrusvariety.ucr.edu |archive-date=8 February 2022 |archive-url=https://web.archive.org/web/20220208152714/https://citrusvariety.ucr.edu/citrus/buddha.html |url-status=live }}</ref>
[[File:Buddhahand2.jpg|thumb|[[Fingered citron]]]]
==== In Hinduism ====
In Nepal, the citron ({{Langx|ne|बिमिरो|translit=bimiro}}) is worshipped during the [[Bhai Tika]] ceremony during [[Tihar (festival)|Tihar]].<ref>{{Cite web |title=बिमिरो पूजासँगै खाउँ पनि! |url=https://shikshakmasik.com/3599/esewa.com.np |access-date=26 October 2022 |website=shikshakmasik.com |language=ne |archive-date=26 October 2022 |archive-url=https://web.archive.org/web/20221026122647/https://shikshakmasik.com/3599/esewa.com.np |url-status=live }}</ref> The worship is thought to stem from the belief that it is a favorite of [[Yama]], Hindu god of death, and his sister [[Yamuna in Hinduism|Yami]].<ref>{{Cite web |last=Nasana |date=29 October 2016 |title=Decoding Bhai Tika symbols |url=https://thehimalayantimes.com/lifestyle/decoding-bhai-tika-symbols-tihar-festival |access-date=5 March 2024 |website=The Himalayan Times |language=en |archive-date=22 September 2023 |archive-url=https://web.archive.org/web/20230922082629/https://thehimalayantimes.com/lifestyle/decoding-bhai-tika-symbols-tihar-festival |url-status=live }}</ref>

=== Perfumery ===
For many centuries, citron's fragrant essential oil ('''oil of cedrate''') has been used in perfumery, the same oil that was used medicinally for its antibiotic properties. Its major constituent is [[limonene]].<ref>{{cite journal |author1=Inouye, S. |author2=Takizawa, T. |author3=Yamaguchi, H. |year=2001 |title=Antibacterial activity of essential oils and their major constituents against respiratory tract pathogens by gaseous contact |journal=Journal of Antimicrobial Chemotherapy |volume=47 |issue=5 |pages=565–573 |doi=10.1093/jac/47.5.565 |pmid=11328766 |doi-access= }}</ref>

== Gallery ==
<gallery heights="120" mode="packed-hover">
File:Cedri BMK.jpg|In a German market, for culinary use
File:4642 - Cedri al mercato di Ortigia, Siracusa - Foto Giovanni Dall'Orto, 20 marzo 2014.jpg|In fruit market of Italy
File:Citrons leaves.jpg|[[Naxos]] citrons and leaf
File:Lipari-Citrons (3).jpg|Citron or [[citrus hybrid|hybrid]] in Sicily
File:മാതളനാരകം.JPG|A wild citron in India
File:Cidra flor.JPG|Citron flowers
File:Citrus 3859.JPG|Unknown citron type in pot
File:Cédrat.jpg|A [[Corsican citron]]
File:Bijora.jpg|Bijora - Citron fruit for sale at Bhujpur, [[Kutch district|Kutch]], [[Gujarat]], India
File:Galgal Lemon.jpg|Citron growing in [[Uttarakhand]],
</gallery>

== Citations ==
{{Reflist|30em}}

== Further reading ==
* H. Harold Hume, ''[https://books.google.com/books?id=Y6c4AAAAMAAJ&dq=greek+citron&pg=PA59 Citrus Fruits and Their Culture]''
* Frederick J. Simoons, ''[https://books.google.com/books?id=Fo087ZxohA4C&dq=citron+mesopotamia&pg=PA200 Food in China: A Cultural and Historical Inquiry]''
* Pinhas Spiegel-Roy, Eliezer E. Goldschmidt, ''[https://books.google.com/books?id=S0-h00_-3CUC&pg=PA4 Biology of Citrus]''
* Alphonse de Candolle, ''[https://books.google.com/books?id=kqcMAAAAYAAJ&dq=citrus+medica+mesopotamia&pg=PA178 Origin of Cultivated Plants]''

== External links ==
{{Wikispecies|Citrus medica}}
{{Commons category multi|Citrus medica|Citrons (Citrus medica)}}
* [https://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?10745 USDA Plants Profile – ''Citrus medica''] {{Webarchive |url=https://web.archive.org/web/20150924133703/http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?10745 |date=24 September 2015 }}
* [http://www.hort.purdue.edu/newcrop/morton/citron.html "Citron"] Purdue University
* [https://web.archive.org/web/20070822234415/http://plantbiology.ucr.edu/people/?Roose#CitrusDiversity University of California- "Citrus Diversity"]
*[https://web.archive.org/web/20110606041237/http://www.flavorandfortune.com/dataaccess/article.php?ID=162 Buddha's Hand citron] by [[David Karp (pomologist)]]

{{Citrus}}
{{Taxonbar|from=Q150064}}

[[Category:Citron| ]]
[[Category:Citrus]]
[[Category:Essential oils]]
[[Category:False friends]]
[[Category:Four species (Sukkot)]]
[[Category:Fruit trees]]
[[Category:Fruits originating in Asia]]
[[Category:Garden plants of Asia]]
[[Category:Medicinal plants of Asia]]
[[Category:Ornamental trees]]
[[Category:Perfumes]]
[[Category:Sukkot]]