Editing Hybrid (biology) (section)

===In plants===
[[File:Platanus xhispanica in Lucenec9.jpg|thumb|upright|The London plane [[Platanus × hispanica|''Platanus'' × ''hispanica'']], is a natural hybrid, popular for street planting.]]
{{further|List of plant hybrids}}

Plant species hybridize more readily than animal species, and the resulting hybrids are fertile more often. Many plant species are the result of hybridization, combined with [[polyploidy]], which duplicates the chromosomes. Chromosome duplication allows orderly meiosis and so viable seed can be produced.<ref name="Goulet2016">{{cite journal |last1=Goulet |first1=Benjamin E. |last2=Roda |first2=Federico |last3=Hopkins |first3=Robin |title=Hybridization in Plants: Old Ideas, New Techniques |journal=Plant Physiology |date=2016 |volume=173 |issue=1 |pages=65–78 |doi=10.1104/pp.16.01340 |pmid=27895205 |pmc=5210733}}</ref>

[[Hybrid name|Plant hybrids are generally given names]] that include an "×" (not in italics), such as [[Platanus × hispanica|''Platanus'' × ''hispanica'']] for the London plane, a natural hybrid of ''[[Platanus orientalis|P. orientalis]]'' (oriental plane) and ''[[Platanus occidentalis|P. occidentalis]]'' (American sycamore).<ref>{{cite book |last1=McNeill |first1=J. |last2=Barrie |first2=F. R. |last3=Buck |first3=W. R. |last4=Demoulin |first4=V. |last5=Greuter |first5=W. |last6=Hawksworth |first6=D. L. |last7=Herendeen |first7=P. S. |last8=Knapp |first8=S. |last9=Marhold |first9=K. |last10=Prado |first10=J. |last11=Prud'homme Van Reine |first11=W. F. |last12=Smith |first12=G. F. |last13=Wiersema |first13=J. H. |last14=Turland |first14=N. J. |url= http://www.iapt-taxon.org/nomen/main.php?page=title |title=International Code of Nomenclature for algae, fungi, and plants (Melbourne Code) adopted by the Eighteenth International Botanical Congress Melbourne, Australia, July 2011 |publisher=A.R.G. Gantner |date=2012 |isbn=9783874294256 |volume=Regnum Vegetabile 154 |access-date=19 March 2017 |archive-url= https://web.archive.org/web/20181225103142/https://www.iapt-taxon.org/nomen/main.php?page=title |archive-date=25 December 2018 |url-status=live}}</ref><ref>{{cite web |title='Columbia' and 'Liberty' Planetree |url= http://www.usna.usda.gov/Newintro/platanus.pdf |publisher=U.S. National Arboretum |access-date=19 March 2017 |date=1999 |archive-date=15 March 2017 |archive-url= https://web.archive.org/web/20170315015908/http://www.usna.usda.gov/Newintro/platanus.pdf |url-status=live}}</ref> The parent's names may be kept in their entirety, as seen in [[Prunus persica × Prunus americana|''Prunus persica'' ×  ''Prunus americana'']], with the female parent's name given first, or if not known, the parent's names given alphabetically.<ref>{{cite book |last=Gledhill |first=David |date=2008 |title=The Names of Plants |url= https://epdf.tips/names-of-plants.html |publisher=Cambridge University Press |page=23 |isbn=9780521685535 |access-date=20 November 2018 |archive-date=20 November 2018 |archive-url= https://web.archive.org/web/20181120180210/https://epdf.tips/names-of-plants.html |url-status=live}}</ref>

Plant species that are genetically compatible may not hybridize in nature for various reasons, including geographical isolation, differences in flowering period, or differences in [[pollinator]]s. Species that are brought together by humans in gardens may hybridize naturally, or hybridization can be facilitated by human efforts, such as altered flowering period or artificial pollination. Hybrids are sometimes created by humans to produce improved plants that have some of the characteristics of each of the parent species. Much work is now being done with hybrids between crops and their wild relatives to improve disease resistance or [[climate resilience]] for both agricultural and horticultural crops.<ref>{{cite journal |last1=Warschefsky |first1=E. |last2=Penmetsa |first2=R. V. |last3=Cook |first3=D. R. |last4=von Wettberg |first4=E. J. B. |title=Back to the wilds: Tapping evolutionary adaptations for resilient crops through systematic hybridization with crop wild relatives |journal=American Journal of Botany |date=8 October 2014 |volume=101 |issue=10 |pages=1791–1800 |doi=10.3732/ajb.1400116 |pmid=25326621|doi-access=free}}</ref>

Some [[list of plant hybrids|crop plants are hybrids]] from different genera (intergeneric hybrids), such as [[Triticale]], × ''Triticosecale'', a wheat–[[rye]] hybrid.<ref>{{cite journal |last=Stace |first=C. A. |author-link=Clive A. Stace |date=1987 |title=Triticale: A Case of Nomenclatural Mistreatment |journal=Taxon |volume=36 |issue=2 |pages=445–452 |jstor=1221447 |doi=10.2307/1221447|bibcode=1987Taxon..36..445S }}</ref> Most modern and ancient wheat breeds are themselves hybrids; [[bread wheat]], ''Triticum aestivum'', is a hexaploid hybrid of three wild grasses.<ref name="Gornicki" /> Several commercial fruits including [[loganberry]] (''Rubus'' × ''loganobaccus'')<ref>{{cite journal |last=Darrow |first=G.M. |date=1955 |title=Blackberry—raspberry hybrids |journal=Journal of Heredity |volume=46 |issue=2 |pages=67–71 |doi=10.1093/oxfordjournals.jhered.a106521}}</ref> and [[grapefruit]] (''Citrus'' × ''paradisi'')<ref>{{cite book |last1=Carrington |first1=Sean |last2=Fraser |first2=Henry C. |title=A~Z of Barbados Heritage |date=2003 |publisher=Macmillan Caribbean |isbn=9780333920688 |pages=90–91 |chapter=Grapefruit}}</ref> are hybrids, as are garden herbs such as [[peppermint]] (''Mentha'' × ''piperita''),<ref>{{cite web|title=Mint Genomics Resource: Species|url= http://langelabtools.wsu.edu/mgr/species|publisher=Lange Laboratory, Washington State University |access-date=20 March 2017 |archive-url= https://web.archive.org/web/20170321081239/http://langelabtools.wsu.edu/mgr/species|archive-date=21 March 2017 |url-status=dead}}</ref> and trees such as the [[Platanus × hispanica|London plane]] (''Platanus'' × ''hispanica'').<ref>{{cite web |last=Hull |first=R. |date=2009 |title=A Short Guide to the London Plane |url= http://www.treetree.co.uk/treetree_downloads/The_London_Plane.pdf |url-status=live |archive-url= https://web.archive.org/web/20191206082115/http://www.treetree.co.uk/treetree_downloads/The_London_Plane.pdf |archive-date=6 December 2019 |access-date=2 February 2016}}</ref><ref>{{cite web |last=Venables |first=B. |date=4 March 2015 |title=The Secret History of the London Plane Tree |url= http://londonist.com/2015/03/the-secret-history-of-the-london-plane-tree |url-status=dead |archive-url= https://web.archive.org/web/20160202074555/http://londonist.com/2015/03/the-secret-history-of-the-london-plane-tree |archive-date=2 February 2016 |access-date=2 February 2016 |publisher=Londonist}}</ref> Among many natural plant hybrids is ''[[Iris albicans]]'', a sterile hybrid that spreads by rhizome division,<ref>{{cite web |title=Legacy Bulbs Six |url= http://pacificbulbsociety.org/pbswiki/index.php/LegacyBulbsSix|publisher=Pacific Bulb Society |access-date=20 March 2017 |archive-date=26 December 2016 |archive-url= https://web.archive.org/web/20161226211458/http://www.pacificbulbsociety.org/pbswiki/index.php/LegacyBulbsSix |url-status=live}}</ref> and ''[[Oenothera lamarckiana]]'', a flower that was the subject of important experiments by [[Hugo de Vries]] that produced an understanding of polyploidy.<ref name="Sirks2013">{{cite book |last=Sirks |first=M. J. |title=General Genetics |url= https://books.google.com/books?id=6dDoCAAAQBAJ&pg=PA408 |date=2013 |publisher=Springer |isbn=9789401575874 |page=408 |access-date=20 March 2017 |archive-date=20 March 2017 |archive-url= https://web.archive.org/web/20170320235024/https://books.google.com/books?id=6dDoCAAAQBAJ&pg=PA408 |url-status=live}}</ref>

<gallery mode="packed">
File:Trilliumhybrid2.jpg|A sterile hybrid between ''[[Trillium cernuum]]'' and ''[[Trillium grandiflorum|T.&nbsp;grandiflorum]]''{{citation needed|date=September 2019}}
File:Lily Lilium 'Citronella' Flower.jpg|An ornamental lily hybrid known as ''Lilium'' 'Citronella'<ref>{{cite web |url= http://www.pacificbulbsociety.org/pbswiki/index.php/LiliumHybrids |title=Lilium Hybrids |publisher=Pacific Bulb Society |access-date=22 March 2015 |archive-date=11 March 2015 |archive-url= https://web.archive.org/web/20150311030853/http://www.pacificbulbsociety.org/pbswiki/index.php/LiliumHybrids |url-status=live}}</ref>
</gallery>

Sterility in a non-polyploid hybrid is often a result of chromosome number; if parents are of differing chromosome pair number, the offspring will have an odd number of chromosomes, which leaves them unable to produce chromosomally balanced [[gamete]]s.<ref>{{cite web |url= http://www.colorado.edu/MCDB/MCDB2150Fall/notes00/L0033.html |title=University of Colorado Principles of Genetics (MCDB 2150) Lecture 33: Chromosomal changes: Monosomy, Trisomy, Polyploidy, Structural Changes |publisher=[[University of Colorado]] |date=21 November 2000 |archive-url= https://web.archive.org/web/20121014211310/http://www.colorado.edu/MCDB/MCDB2150Fall/notes00/L0033.html |archive-date=14 October 2012}}</ref> While that is undesirable in a crop such as wheat, for which growing a crop that produces no seeds would be pointless, it is an attractive attribute in some fruits. [[Triploid]] [[banana]]s and [[watermelon]]s are intentionally bred because they produce no seeds and are also [[parthenocarpy|parthenocarpic]].<ref>{{cite journal |last1=Burr |first1=Benjamin |last2=Burr |first2=Frances |title=How do seedless fruits arise and how are they propagated? |journal=Scientific American |date=2 October 2000 |url= https://www.scientificamerican.com/article/how-do-seedless-fruits-ar/ |access-date=20 March 2017 |archive-date=20 March 2017 |archive-url= https://web.archive.org/web/20170320233815/https://www.scientificamerican.com/article/how-do-seedless-fruits-ar/ |url-status=live}}</ref>