Editing Rose (section)

== Botany ==

The [[leaves]] are borne alternately on the stem. In most species, they are {{convert|5|to|15|cm}} long, [[pinnate]], with (3–) 5–9 (−13) leaflets and basal [[stipule]]s; the leaflets usually have a serrated margin, and often a few small prickles on the underside of the stem. Most roses are [[deciduous]] but a few (particularly from [[Southeast Asia]]) are [[evergreen]] or nearly so.

=== Thorns ===
The sharp growths along a rose stem, though commonly called "thorns", are technically [[thorns, spines and prickles|prickles]], outgrowths of the [[Epidermis (botany)|epidermis]] (the outer layer of tissue of the stem), unlike true thorns, which are [[Aerial stem modification|modified stems]]. Rose prickles are typically sickle-shaped hooks, which aid the rose in hanging onto other vegetation when growing over it. Some species such as ''[[Rosa rugosa]]'' and ''[[Rosa pimpinellifolia|R.&nbsp;pimpinellifolia]]'' have densely packed straight prickles, probably an adaptation to reduce [[Browsing (herbivory)|browsing]] by animals, but also possibly an adaptation to trap wind-blown [[sand]] and so reduce [[erosion]] and protect their [[root]]s (both of these species grow naturally on [[coast]]al [[dune|sand dunes]]). Despite the presence of prickles, roses are frequently browsed by [[deer]]. A few species of roses have only vestigial prickles that have no points.{{citation needed|date=February 2025}}

Plant geneticist Zachary Lippman of [[Cold Spring Harbor Laboratory]] found that prickles are controlled by the LOG gene.<ref>{{cite journal |journal=Science |last1=Satterlee |first1=J.W. |last2=Alonso |first2=D. |last3=Gramazio |first3=P. |title=Convergent evolution of plant prickles by repeated gene co-option over deep time. |date=2024 |volume=385 |issue=6708 |page=1663 |doi=10.1126/science.ado1663 |pmid=39088611 |pmc=11305333 |bibcode=2024Sci...385o1663S }}</ref><ref>{{cite news |last1=Zimmer |first1=Carl |title=How Did Roses Get Their Thorns? |url=https://www.nytimes.com/2024/08/01/science/how-did-roses-get-their-thorns.html |access-date=1 September 2024 |work=The New York Times |date=August 1, 2024}}</ref> Blocking the LOG gene in roses reduced the thorns (large prickles) into tiny buds.

{{gallery|mode=packed
|Rose Prickles.jpg|Rose thorns
|Roseleaves3800px.JPG|Rose leaflets
}}

=== Flower ===
The [[flower]]s of most species have five petals, with the exception of ''[[Rosa omeiensis]]'' and ''[[Rosa sericea]]'', which usually have only four. Each [[petal]] is divided into two distinct lobes and is usually white or pink, though in a few species yellow or red. Beneath the petals are five [[sepals]] (or in the case of some ''Rosa omeiensis'' and ''Rosa sericea'', four). These may be long enough to be visible when viewed from above and appear as green points alternating with the rounded petals. The coloured petals are fused on the axis and arranged in five bundles forming a circle, the petal bundles expand further from each other;<ref name="AJB">{{cite journal |last=Jackson |first=Gemma |title=The morphology of the flowers of ''Rosa'' and certain cloesly related genera |journal=American Journal of Botany |date=October 1934 |volume=21 |issue=8 |pages=453–466 |doi=10.1002/j.1537-2197.1934.tb04973.x |bibcode=1934AmJB...21..453J |url=https://bsapubs.onlinelibrary.wiley.com/doi/abs/10.1002/j.1537-2197.1934.tb04973.x}}</ref>{{rp|458-459}} the petals form a cup or disc surrounding the [[gynoecium]].<ref name="AJB"/>{{rp|453}} There are multiple [[Ovary (plants)#Superior ovary|superior]] ovaries that develop into [[achene]]s.<ref>{{cite book |last=Mabberley |first=D. J. |year=1997 |title=The Plant-Book: A Portable Dictionary of the Vascular Plants |url=https://archive.org/details/plantbookportabl00mabb |url-access=registration |publisher=Cambridge University Press |location=Cambridge|isbn=978-0-521-41421-0 }}</ref>

{{gallery|mode=packed
|Rose hip 02 ies.jpg|Longitudinal section of a developing rose hip
|Roses Boutons FR 2012.jpg|Exterior view of rose buds
|||A close-up of climbing roses.jpg|A close-up of a climbing rose
}}

=== Reproduction === 
{{no sources section|date=February 2025}}
Roses are insect-pollinated in nature. A fertilized ovary forms a berry-like [[aggregate fruit]] called a "[[rose hip|hip]]". The hips of most species are red, but a few (e.g. ''[[Rosa pimpinellifolia]]'') have dark purple to black hips. Each hip comprises an outer fleshy layer, the [[hypanthium]], which contains 5–160 "seeds" (technically dry single-seeded fruits called [[achene]]s) embedded in a matrix of fine, but stiff, hairs. Rose hips of some species, especially the [[dog rose]] (''Rosa canina'') and [[rugosa rose]] (''R.&nbsp;rugosa''), are very rich in [[vitamin&nbsp;C]], among the richest sources of any plant. The hips are eaten by fruit-eating [[bird]]s such as [[thrush (bird)|thrushes]] and [[waxwing]]s, which then disperse the [[seed]]s in their droppings.

Many of the domestic [[cultivar]]s do not produce hips, as the [[flower]]s are too tightly petalled to provide access for [[pollination]] and the plants can only propagate through human-made [[cutting (plant)|cuttings]].{{verify inline|date=February 2025}}

=== Evolution ===
The oldest remains of roses are from the Late [[Eocene]] [[Florissant Formation]] of Colorado.<ref>{{Cite journal|last1=DeVore|first1=M. L.|last2=Pigg|first2=K. B.|date=July 2007|title=A brief review of the fossil history of the family Rosaceae with a focus on the Eocene Okanogan Highlands of eastern Washington State, USA, and British Columbia, Canada|url=http://link.springer.com/10.1007/s00606-007-0540-3|journal=Plant Systematics and Evolution|language=en|volume=266|issue=1–2|pages=45–57|doi=10.1007/s00606-007-0540-3|bibcode=2007PSyEv.266...45D |s2cid=10169419 |issn=0378-2697}}</ref> Roses were present in [[Europe]] by the early [[Oligocene]].<ref>{{Cite journal|last1=Kellner|first1=A.|last2=Benner|first2=M.|last3=Walther|first3=H.|last4=Kunzmann|first4=L.|last5=Wissemann|first5=V.|last6=Ritz|first6=C. M.|date=March 2012|title=Leaf Architecture of Extant Species of Rosa L. and the Paleogene Species Rosa lignitum Heer (Rosaceae)|url=https://www.journals.uchicago.edu/doi/10.1086/663965|journal=International Journal of Plant Sciences |volume=173|issue=3|pages=239–250|doi=10.1086/663965|bibcode=2012IJPlS.173..239K |s2cid=83909271 |issn=1058-5893}}</ref>

Today's garden roses come from 18th-century China.<ref>{{cite web|url=https://web.extension.illinois.edu/roses/history.cfm |title=The History of Roses — Our Rose Garden |work=University of Illinois Extension |date= |access-date=2021-02-26}}</ref> Among the old Chinese garden roses, the Old Blush group is the most primitive, while newer groups are the most diverse.<ref>{{cite journal | title=Genetic relationships and evolution of old Chinese garden roses based on SSRs and chromosome diversity – Scientific Reports | journal=Scientific Reports | date=2017  | volume=7 | issue=1 | page=15437 | doi=10.1038/s41598-017-15815-6 | last1=Tan | first1=Jiongrui | last2=Wang | first2=Jing | last3=Luo | first3=Le | last4=Yu | first4=Chao | last5=Xu | first5=Tingliang | last6=Wu | first6=Yuying | last7=Cheng | first7=Tangren | last8=Wang | first8=Jia | last9=Pan | first9=Huitang | last10=Zhang | first10=Qixiang | pmid=29133839 | pmc=5684293 }}</ref>

===Genome===

A study of the patterns of [[natural selection]] in the [[genome]] of roses indicated that [[gene]]s related to [[DNA repair|DNA damage repair]] and stress adaptation have been positively selected, likely during their domestication.<ref name = Li2018>{{cite journal |vauthors=Li S, Zhong M, Dong X, Jiang X, Xu Y, Sun Y, Cheng F, Li DZ, Tang K, Wang S, Dai S, Hu JY |title=Comparative transcriptomics identifies patterns of selection in roses |journal=BMC Plant Biol |volume=18 |issue=1 |pages=371 |date=December 2018 |pmid=30579326 |pmc=6303930 |doi=10.1186/s12870-018-1585-x |doi-access=free |bibcode=2018BMCPB..18..371L }}</ref>  This rapid evolution may reflect an adaptation to genome confliction resulting from frequent intra- and inter-species hybridization and switching environmental conditions of growth.<ref name = Li2018/>

=== Species ===
{{Main|List of Rosa species}}
[[File:Redoute - Rosa gallica purpuro-violacea magna.jpg|thumb|upright|''Rosa gallica'' 'Evêque', painted by [[Pierre-Joseph Redouté|Redouté]]]]

The genus ''Rosa'' is composed of 140–180 species and divided into four subgenera:<ref>{{cite book |last1=Leus |first1=Leen |last2=Van Laere |first2=Katrijn |last3=De Riek |first3=Jan |last4=Van Huylenbroeck |first4=Johan |editor1-last=Van Huylenbroeck |editor1-first=Johan |title=Ornamental Crops |date=2018 |publisher=Springer |isbn=978-3-319-90697-3 |pages=719–767 See p. 720 |chapter=Rose |series=Handbook of Plant Breeding |chapter-url=https://link.springer.com/chapter/10.1007/978-3-319-90698-0_27 |volume=11 |doi=10.1007/978-3-319-90698-0_27}}</ref>

* ''Hulthemia'' (formerly ''Simplicifoliae'', meaning "with single leaves") containing two species from [[Southwest Asia]], ''[[Rosa persica]]'' and ''[[Rosa berberifolia]]'', which are the only roses without [[compound leaves]] or [[stipule]]s.<ref>{{Cite web |title=Rosa persica - Trees and Shrubs Online |url=https://www.treesandshrubsonline.org/articles/rosa/rosa-persica/ |access-date=2024-05-19 |website=www.treesandshrubsonline.org}}</ref>
* ''Hesperrhodos'' (from the [[Greek (language)|Greek]] for "western rose") contains ''[[Rosa minutifolia]]'' and ''[[Rosa stellata]]'', from [[North America]].
* ''Platyrhodon'' (from the [[Greek (language)|Greek]] for "flaky rose", referring to flaky bark) with one species from east Asia, ''[[Rosa roxburghii]]'' (also known as the chestnut rose).
* ''Rosa'' (the [[biological type|type]] subgenus, sometimes incorrectly called ''Eurosa'') containing all the other roses. This subgenus is subdivided into 11 sections.
** ''Banksianae''&nbsp;– white and yellow flowered roses from China.
** ''Bracteatae''&nbsp;– three species, two from China and one from India.
** ''[[Rosa sect. Caninae|Caninae]]''&nbsp;– pink and white flowered species from Asia, Europe and [[North Africa]].
** ''Carolinae''&nbsp;– white, pink, and bright pink flowered species all from North America.
** ''Chinensis''&nbsp;– white, pink, yellow, red and mixed-colour roses from China and [[Burma]].
** ''Gallicanae''&nbsp;– pink to crimson and striped flowered roses from western Asia and Europe.
** ''Gymnocarpae''&nbsp;– one species in western North America (''[[Rosa gymnocarpa]]''), others in east Asia.
** ''Laevigatae''&nbsp;– a single white flowered species from China.
** ''Pimpinellifoliae''&nbsp;– white, pink, bright yellow, mauve and striped roses from Asia and Europe.
** ''Rosa'' (syn. sect. ''Cinnamomeae'')&nbsp;– white, pink, lilac, mulberry and red roses from everywhere but North Africa.
** ''Synstylae''&nbsp;– white, pink, and crimson flowered roses from all areas.