Editing Fruit (section)

== Development ==
A fruit results from the fertilizing and maturing of one or more flowers. The [[gynoecium]], which contains the ''[[stigma (botany)#Description|stigma-style-ovary]]'' system, is centered in the flower-head, and it forms all or part of the fruit.<ref>Esau, K. 1977. ''Anatomy of seed plants''. John Wiley and Sons, New York.</ref> Inside the [[ovary (botany)|ovary(ies)]] are one or more [[ovule]]s. Here begins a complex sequence called ''[[double fertilization]]'': a female [[double fertilization|gametophyte]] produces an egg cell for the purpose of fertilization.<ref>[http://www.palaeos.com/Plants/Lists/Glossary/GlossaryL.html#M] {{webarchive|url=https://web.archive.org/web/20101220200017/http://www.palaeos.com/Plants/Lists/Glossary/GlossaryL.html#M|date=December 20, 2010}}</ref><!--January 2012, the http://palaeos.com/ web site requests that links like this not be corrected until their major overhaul is completed and a public announcement made.--> (A female gametophyte is called a ''[[double fertilization#Megagametophyte|megagametophyte]]'', and also called the ''[[embryo sac]]''.) After double fertilization, the ovules will become seeds.

Ovules are fertilized in a process that starts with [[pollination]], which is the movement of pollen from the stamens to the stigma-style-ovary system within the flower-head. After pollination, a [[pollen tube]] grows from the (deposited) pollen through the stigma down the style into the ovary to the ovule. Two sperm are transferred from the pollen to a megagametophyte. Within the megagametophyte, one sperm unites with the egg, forming a [[zygote]], while the second sperm enters the central cell forming the endosperm mother cell, which completes the double fertilization process.<ref>{{cite book |author=Mauseth, James D. |title=Botany: an introduction to plant biology |year=2003 |publisher=Jones and Bartlett Publishers |location=Boston |isbn=978-0-7637-2134-3 |page=258}}</ref><ref>{{cite book |author1=Rost, Thomas L. |author2=Weier, T. Elliot |author3=Weier, Thomas Elliot |title=Botany: a brief introduction to plant biology |year=1979 |publisher=Wiley |location=New York |isbn=978-0-471-02114-8 |pages=[https://archive.org/details/botanybriefintro00rost/page/135 135–37] |url=https://archive.org/details/botanybriefintro00rost/page/135 }}</ref> Later, the zygote will give rise to the embryo of the seed, and the endosperm mother cell will give rise to [[endosperm]], a nutritive tissue used by the embryo.

Fruit formation is associated with [[meiosis]], a central aspect of [[Sexual reproduction|sexual]] reproduction in flowering plants. During meiosis [[homologous chromosome]]s replicate, [[genetic recombination|recombine]] and randomly segregate, and then undergo segregation of [[sister chromatids]] to produce [[haploid]] cells.<ref>{{cite journal |vauthors=Wang Y, van Rengs WM, Zaidan MW, Underwood CJ |title=Meiosis in crops: from genes to genomes |journal=J Exp Bot |volume=72 |issue=18 |pages=6091–6109 |date=September 2021 |pmid=34009331 |pmc=8483783 |doi=10.1093/jxb/erab217 |url=}}</ref> Union of haploid nuclei from [[pollen]] and [[ovule]] ([[fertilisation]]), occurring either by [[autogamy|self]]- or cross-[[pollination]], leads to the formation of a diploid [[zygote]] that can then develop into an [[embryo]] within the emerging seed. Repeated fertilisations within the [[ovary]] are accompanied by maturation of the ovary to form the fruit.

As the ovules develop into seeds, the ovary begins to ripen and the ovary wall, the ''pericarp'', may become fleshy (as in berries or [[drupe]]s), or it may form a hard outer covering (as in nuts). In some multi-seeded fruits, the extent to which a fleshy structure develops is proportional to the number of fertilized ovules.<ref>{{cite book |last=Mauseth |title=Botany |url=https://books.google.com/books?id=0DfYJsVRmUcC&pg=PP14 |pages=Chapter 9: Flowers and Reproduction |no-pp=true |isbn=978-0-7637-2134-3 |year=2003 |publisher=Jones & Bartlett Learning |access-date=2020-05-09 |archive-date=2024-01-30 |archive-url=https://web.archive.org/web/20240130053426/https://books.google.com/books?id=0DfYJsVRmUcC&pg=PP14#v=onepage&q&f=false |url-status=live }}</ref> The pericarp typically is differentiated into two or three distinct layers; these are called the ''exocarp'' (outer layer, also called epicarp), ''mesocarp'' (middle layer), and ''endocarp'' (inner layer).

In some fruits, the [[sepal]]s, [[petal]]s, [[stamen]]s or [[Gynoecium|the style]] of the flower fall away as the fleshy fruit ripens. However, for simple fruits derived from an ''[[inferior ovary#Classification based on position|inferior ovary]]'' – i.e., one that lies {{em|below}} the attachment of other floral parts – there are parts (including petals, sepals, and stamens) that fuse with the ovary and ripen with it. For such a case, when floral parts other than the ovary form a significant part of the fruit that develops, it is called an [[#accessory fruit|accessory fruit]]. Examples of accessory fruits include apple, rose hip, strawberry, and pineapple.

Because several parts of the flower besides the ovary may contribute to the structure of a fruit, it is important to understand how a particular fruit forms.<ref name="Mauseth271" /> There are three general modes of fruit development:

* [[gynoecium#Types|Apocarpous]] fruits develop from a ''single flower'' (while having one or more separate, unfused, carpels); they are the [[#Simple fruit|simple fruits]].
* [[gynoecium#Types|Syncarpous]] fruits develop from a ''single [[gynoecium]]'' (having two or more carpels fused together).
* [[#Multiple fruits|Multiple fruits]] form from many flowers – i.e., an inflorescence of flowers.

<gallery widths="200px" heights="200px">
File:Nectarine Fruit Development.jpg|The development sequence of a typical [[drupe]], the [[nectarine]] (''Prunus persica'') over a 7.5-month period, from bud formation in early winter to fruit [[ripening]] in midsummer
File:Mature flower diagram.svg|right|The parts of a flower, showing the stigma-style-ovary system.
File:Pome apples text.jpg|An apple is a simple, fleshy fruit. Key parts are the epicarp, or exocarp, or outer skin (not labelled); and the mesocarp and endocarp (labelled).
image:Ovary position.svg|right|upright 1.5|Insertion point: There are three positions of insertion of the ovary at the base of a flower: I superior; II half-inferior; III inferior. The 'insertion point' is where the [[androecium]] parts (a), the petals (p), and the sepals (s) all converge and attach to the receptacle (r). (Ovary=gynoecium (g).)
File:Noni fruit dev.jpg|upright 1.5|In the [[noni]], flowers are produced in time-sequence along the stem. It is possible to see a progression of flowering, fruit development, and fruit ripening.
Tweelinggroei appels.jpg|Twin apples
</gallery>