View source for Drupe

{{short description|Fleshy fruit with hard inner layer (endocarp or stone) surrounding the seed}}
{{Refimprove|date=November 2011}}
[[Image:Drupe fruit diagram.svg|lang=en|250px|thumb|Diagram of a typical drupe ([[peach]]), showing both [[fruit]] and [[seed]]]]
[[Image:Nectarine Fruit Development.jpg|right|thumb|300px|The development sequence of a typical drupe, a smooth-skinned ([[Peach#Nectarines|nectarine]]) type of peach (''Prunus persica'') over a {{frac|7|1|2}}-month period, from bud formation in early winter to fruit ripening in midsummer]]
In [[botany]], a '''drupe''' (or '''stone fruit''') is a type of [[fruit]] in which an outer fleshy part ([[exocarp]], or skin, and [[mesocarp]], or flesh) surrounds a single shell (the ''pip'' (UK), ''pit'' (US), ''stone'', or ''[[pyrena]]'') of hardened [[endocarp]] with a [[seed]] (''kernel'') inside. Drupes do not split open to release the seed, i.e., they are [[dehiscence (botany)|indehiscent]].<ref name="Stern">{{cite book |title=Introductory Plant Biology |url=https://archive.org/details/introductoryplan00ster |url-access=registration |edition=Seventh |first=Kingsley R. |last=Stern |location=Dubuque |publisher=Wm. C. Brown |year=1997 |isbn=0-07-114448-X }}</ref>  These fruits usually develop from a single [[carpel]], and mostly from flowers with [[Superior ovary|superior ovaries]]<ref name="Stern" /> ([[polypyrenous drupe]]s are exceptions).
The definitive characteristic of a drupe is that the hard, woody ([[lignified]]) stone is derived from the [[Ovary (botany)|ovary]] wall of the [[flower]]. In an [[aggregate fruit]], which is composed of small, individual drupes (such as a [[raspberry]]), each individual is termed a '''drupelet''', and may together form an aggregate fruit. Such fruits are often termed ''[[berries]]'', although botanists use a [[Berry (botany)|different definition of ''berry'']]. Other fleshy fruits may have a stony enclosure that comes from the seed coat surrounding the seed, but such fruits are not drupes.
[[Flowering plant]]s that produce drupes include [[coffea arabica|coffee]], [[jujube]], [[mango]], [[olive]], most palms (including [[açaí]], [[Date Palm|date]], [[sabal]] and [[oil palm]]s), [[pistachio]], [[white sapote]], [[cashew]], and all members of the genus ''[[Prunus]]'', including the [[almond]], [[apricot]], [[cherry]], [[damson]], [[peach]], [[nectarine]], and [[plum]].
The term '''drupaceous''' is applied to a fruit having the structure and texture of a drupe,<ref name=FNAG>{{cite web |first1=Robert W. |last1=Kiger |first2=Duncan M. |last2=Porter |date=2001 |title=Find term 'drupaceous' |website=Categorical Glossary for the Flora of North America Project |url=http://fmhibd.library.cmu.edu/HIBD-DB/FNA/findrecords.php |access-date=2015-08-14 |name-list-style=amp }}</ref> but which does not precisely fit the definition of a drupe.
==Terminology==
The boundary between a drupe and a berry is not always clear. Thus, some sources describe the fruit of species from the genus ''[[Persea]]'', which includes the [[avocado]], as a drupe,<ref name="FNA">{{cite book |first1=B. Eugene |last1=Wofford |contribution=Persea |contribution-url=http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=124627 |access-date=2017-03-29 |editor-last=Flora of North America Editorial Committee|title=Flora of North America ''(online)'' |publisher=eFloras.org }}
</ref> others describe avocado fruit as a berry.<ref name=Arms08/> One definition of ''berry'' requires the endocarp to be less than {{Convert|2|mm|abbr=on|frac=32}} thick, other fruits with a stony endocarp being drupes.<ref name=Been10>{{Cite book |last=Beentje |first=Henk |year=2010 |title=The Kew Plant Glossary |location=Richmond, Surrey |publisher=[[Royal Botanic Gardens, Kew]] |isbn=978-1-84246-422-9 }}</ref>  In marginal cases, terms such as ''drupaceous'' or ''drupe-like'' may be used.<ref name=FNAG/><ref name=Been10/>
The term '''stone fruit''' (also '''stonefruit''') can be a synonym for drupe or, more typically, it can mean just the fruit of the genus ''Prunus''.
'''Freestone''' refers to a drupe having a stone which can be removed from the flesh with ease. The flesh is not attached to the stone and does not need to be cut to free the stone. Freestone varieties of fruits are preferred for uses that require careful removal of the stone, especially if removal will be done by hand. Freestone plums are preferred for making homegrown [[prune]]s, and freestone [[sour cherry|sour cherries]] are preferred for making pies and [[cherry soup]].
'''Clingstone''' refers to a drupe having a stone which cannot be easily removed from the flesh. The flesh is attached strongly to the stone and must be cut to free the stone. Clingstone varieties of fruits in the genus ''Prunus'' are preferred as table fruit and for jams, because the flesh of clingstone fruits tends to be more tender and juicy throughout.
'''Tryma''' is a specialized term for such [[Nut (fruit)|nut]]-like drupes that are difficult to categorize. Hickory nuts ([[Carya (genus)|''Carya'']]) and [[walnut]]s (''[[Juglans]]'') in the [[Juglandaceae]] family grow within an outer husk; these fruits are technically drupes or drupaceous nuts, thus are not true botanical [[Nut (fruit)|nuts]].<ref name=Arms08>{{Cite web|title=Identification of Major Fruit Types
| first = W. P. | last = Armstrong
| date = 2008
|url=http://www.waynesword.net/fruitid1.htm|access-date=2023-01-16}}</ref><ref>{{Cite web
| title= Fruits Called Nuts
| date = 2009
| first = W. P. | last = Armstrong
|url=http://www.waynesword.net/ecoph8.htm|access-date=2023-01-16}}</ref>
==Ecology==
Many drupes, with their sweet, fleshy outer layer, attract the attention of animals as a [[food]], and the plant population benefits from the resulting [[seed dispersal|dispersal of its seeds]]. The [[endocarp]] (pit or stone) is sometimes dropped after the fleshy part is eaten, but is often swallowed, passing through the [[digestive tract]], and returned to the soil in [[feces]] with the seed inside unharmed. This passage through the digestive tract can reduce the thickness of the endocarp, thus can aid in germination rates. The process is known as [[Scarification (botany)|scarification]].{{Citation needed|date=May 2023}}
==Examples==
Typical drupes include [[Apricot|apricots]], [[Olive|olives]], [[loquat]], [[Peach|peaches]], [[Plum|plums]], [[Cherry|cherries]], [[Mango|mangoes]], [[Pecan|pecans]], and [[Phyllanthus emblica|amlas]] (Indian gooseberries). <!-- (See the images below.) -->Other examples include sloe (''[[Prunus spinosa]]'') and ivy (''[[Hedera helix]]'').<ref>Clapham, A.R., Tutin, T.G. and Warburg, E.F. 1968. ''Excursion Flora of the British Isles''. Cambridge University Press{{ISBN|0-521-04656-4}}</ref>
The [[coconut]] is also a drupe, but the [[mesocarp]] is fibrous or dry (termed a ''husk''<ref name="Stern" />), so this type of fruit is classified as a simple dry, fibrous drupe. Unlike other drupes, the coconut seed is so large that it is unlikely to be dispersed by being swallowed by [[fauna (animals)|fauna]], but it can float extremely long distances—across oceans.
[[Bramble]] fruits such as the [[blackberry]] and the [[raspberry]] are aggregates of drupelets. <!-- rest of paragraph translated from French Wikipedia [[fr:drupe]] --> The fruit of blackberries and raspberries comes from a single flower whose [[pistil]] is made up of a number of free carpels. However, [[mulberry|mulberries]], which closely resemble blackberries, are not aggregate fruit, but are [[multiple fruit]]s, actually derived from bunches of [[catkin]]s, each drupelet thus belonging to a different flower.
Certain drupes occur in large clusters, as in the case of palm species, where a large array of drupes is found in a cluster. Examples of such large drupe clusters include [[Date palm|dates]], ''[[Jubaea chilensis]]''<ref>C. Michael Hogan. 2008. [http://globaltwitcher.auderis.se/artspec_information.asp?thingid=82831 ''Chilean Wine Palm: Jubaea chilensis'', GlobalTwitcher.com, ed. N. Stromberg] {{webarchive |url=https://web.archive.org/web/20121017013207/http://globaltwitcher.auderis.se/artspec_information.asp?thingid=82831 |date=October 17, 2012 }}</ref> in central Chile and ''[[Washingtonia filifera]]'' in the [[Sonoran Desert]] of North America.
Drupe-like "fruits" are also known in many [[gymnosperm]]s like [[cycad]]s, [[ginkgo]]s and some [[cypress]]es.<ref>{{cite journal |first1=D.L. |last1=Contreras |first2=I.A.P. |last2=Duijnstee |first3=S. |last3=Ranks |first4=C.R. |last4=Marshall |first5=C.V. |last5=Looy |date=February 2017 |title=Evolution of dispersal strategies in conifers: Functional divergence and convergence in the morphology of diaspores |journal=Perspectives in Plant Ecology, Evolution and Systematics |volume=24 |pages=93–117 |doi=10.1016/j.ppees.2016.11.002|doi-access=free |bibcode=2017PPEES..24...93C }}</ref>
==Gallery==
<gallery>
Image:NIEdot325.jpg|Assorted drupes
Image:Autumn Red peaches.jpg|The [[peach]] is a typical drupe (stone fruit)
Image:Prunus - Elena.JPG|'Elena', a freestone [[prune plum]]
Image:Nectarine_stone.jpg|The pit of a [[nectarine]]
Image:Black Pepper (Piper nigrum) fruits.jpg|Unripe drupes of [[black pepper]]
Image:Black Butte blackberry.jpg|'Black Butte' blackberry, a bramble fruit of aggregated drupelets
Image:arecanut.jpg|A ripe [[areca nut]]
File:Ginkgo biloba 007.jpg|[[Ginkgo]] "fruits", often noted as drupe-like
</gallery>
==See also==
* [[Pome]] (polypyrenous drupe)
==References==
{{Reflist|30em}}
==External links==
{{Wiktionary|freestone|clingstone}}
* [https://web.archive.org/web/20201223072054/https://www2.palomar.edu/users/warmstrong/fruitid1.htm Identification of Major Fruit Types] (archived)
* [https://web.archive.org/web/20200315011337/https://www2.palomar.edu/users/warmstrong/ecoph8.htm Fruits Called Nuts] (archived)
* {{Cite NIE|wstitle=Drupe |year=1905 |short=x}}
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[[Category:Drupes| ]]
[[Category:Edible nuts and seeds]]
[[Category:Fruit morphology]]