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[[File:Sangiovese grapevine.jpg|right|thumb|300px|A [[Sangiovese]] grapevine in a vineyard with a cane extended. Prior to this cane developing grape clusters it could have been planted in the ground to propagate by layering.]]
The '''propagation of grapevines''' is an important consideration in commercial [[viticulture]] and [[winemaking]]. Grapevines, most of which belong to the ''[[Vitis vinifera]]'' family, produce one crop of fruit each [[growing season (vine)|growing season]] with a limited life span for individual vines. While some centenarian [[old vine]] examples of [[grape varieties]] exist, most grapevines are between the ages of 10 and 30 years. As vineyard owners seek to replant their vines, a number of techniques are available which may include planting a new [[cutting (plant)|cutting]] that has been selected by either [[clonal (plant)|clonal]] or mass (massal) selection. Vines can also be propagated by [[grafting]] a new plant vine upon existing [[rootstock]] or by [[layering]] one of the [[canes (vine)|canes]] of an existing vine into the ground next to the vine and severing the connection when the new vine develops its own root system.<ref name="WSET">Wine & Spirits Education Trust ''"Wine and Spirits: Understanding Wine Quality"''
In commercial viticulture, grapevines are rarely propagated from [[seedling]]s as each seed contains unique genetic information from its two parent varieties (the flowering parent and the parent that provided the pollen that fertilized the flower) and would, theoretically, be a different variety than either parent. This would be true even if two [[hermaphroditic]] vine varieties, such as [[Chardonnay]], cross pollinated each other. While the grape clusters that would arise from the pollination would be considered Chardonnay any vines that sprang from one of the seeds of the grape berries would be considered a distinct variety other than Chardonnay. It is for this reason that grapevines are usually propagated from cuttings while [[grape breeders]] will utilize seedlings to come up with new grape varieties including [[crossings (plant)|crossings]] that include parents of two varieties within the same species (such as [[Cabernet Sauvignon]] which is a crossing of the ''Vitis vinifera'' varieties [[Cabernet Franc]] and [[Sauvignon blanc]]) or [[hybrid grape]] varieties which include parents from two different ''[[Vitis]]'' species such as the [[Armagnac (brandy)|Armagnac]] grape [[Baco blanc]], which was propagated from the ''vinifera'' grape [[Folle blanche]] and the ''[[Vitis labrusca]]'' variety [[Noah (grape)|Noah]].<ref name="WSET"/>
== Terminology ==
[[File:Pinot noir, Pinot gris and Pinot blanc.png|right|260px|thumb|Pinot gris (center) and Pinot blanc (right) are color mutations of Pinot noir (left).]]
In viticulture, a '''clone''' is single vine that has been selected by a "mother vine" to which it is identically similar. This clone may have been selected deliberately from a grapevine that has demonstrated desirable traits (good [[yields (wine)|yields]], [[grape disease]] resistance, small berry size, etc) and propagated as cuttings from that mother vine. Varieties such as [[Sangiovese]] and [[Pinot noir]] are well known to have a variety of clones. While there maybe slight mutations to differentiate the various clones, all clones are considered genetically part of the same variety (i.e. Sangiovese or Pinot noir).<ref name="Oxford">J. Robinson (ed) ''"The Oxford Companion to Wine"'' Third Edition pgs 183-184 Oxford University Press 2006 ISBN 0-19-860990-6</ref>▼
A '''color mutation''' is a grape variety that while genetically similar to the original variety is considered unique enough to merit being considered its own variety. Both [[Pinot gris]] and [[Pinot blanc]] are color [[Mutation|mutations]] of Pinot noir.<ref name="WSET"/>▼
▲In viticulture, a '''clone''' is a single vine that has been selected
▲A '''color mutation''' is a grape variety that while genetically similar to the original variety is considered unique enough to merit being considered its own variety. Both [[Pinot gris]] and [[Pinot blanc]] are color mutations of Pinot noir.<ref name="WSET"/>
A '''selection massale''' is the opposite of cloning, where growers select cuttings from the mass of the vineyard, or a field blend.
A '''
A '''hybrid''' is a new grape variety that was produced from a cross pollination of two different grape species. In the early history of [[American wine]]making, grape growers would cross the European ''Vitis vinifera'' vines with American vine varieties such as ''Vitis labrusca'' to create French-American hybrids that were more resistant to American grape diseases such as [[downy (mildew)|downy]] and [[powdery mildew]] as well as [[phylloxera]]. When the [[phylloxera epidemic]] of the mid to late 19th century hit Europe, some growers in European wine regions experimented with using hybrids until a solution involving [[grafting]] American [[Rootstock|rootstocks]] to ''vinifera'' varieties was found. Eventually, the use of hybrids in wine production declined with their use formally outlawed by European [[wine law]]s in the 1950s.<ref name="WSET"/><br />[[File:Grape Vine Cuttings.jpg|right|thumb|Young vine cuttings in a nursery]]
As commercial winemakers usually want to work with a desired grape variety that dependably produces a particular crop, most grapevines are propagated by clonal or massal selection of plant material. This can be accomplished in one of three ways.<ref name="WSET"/>▼
== Propagation methods ==
#Cuttings-This involves a [[shoot]] taken from a mother vine and than planted where the shoot will eventually sprout a root system and regenerate itself into a full fledged vine with trunk and [[canopy (vine)|canopy]]. Often new cuttings will be first planted in a nursery where it is allowed to develop for a couple years before being planted in the vineyard.<ref name="WSET"/>▼
▲As commercial winemakers usually want to work with a desired grape variety that dependably produces a particular crop, most grapevines are propagated by clonal or massal selection of plant material. This can be accomplished in one of three ways.<ref name="WSET" />
#Layering-In established vineyards where only a few vines need to be replaced within a row (such as vine lost to machine damage or disease), a new vine can be propagated by bending a cane from a neighboring vine into the ground and covering it with dirt. This segment of vine will soon begin sprouting its own independent root system while still being nourished by the connecting vine. Eventually the connection between the two vines are severed allowing each vine to grow independently.<ref name="WSET"/>▼
=== Cuttings ===
==Clonal versus massal selection==▼
▲
[[File:Vineyard 1.jpg|left|thumb|One criticism of clonal selection is the use of only one or two clones greatly diminishes the genetic diversity of a vineyard.]]▼
Each cutting, taken from a mother vine, is a clone of that vine. The way that a vine grower selects these cuttings can be described as either '''clonal''' or '''massal selection'''. In clonal selection, a ideal plant within a vineyard or nursery that has exhibited the most desirable traits is selected with all cuttings taken from that single plant. In massal (or "mass") selection, cuttings are taken from several vines of the same variety that have collectively demonstrated desirable traits.<ref name="WSET"/>▼
=== Grafting ===
Historically massal selection was the primary means of vineyard propagation, particularly in traditional vineyards where vines are only sporadically replaced, often by layering a cane from a neighboring vine. In the 1950s, the isolation and identification of desirable clones in nurseries and breeding stations lead to an increase in clonal selection with new vineyard plantings seeking out clones from well established vineyards and wine region. This trend towards clonal selection has seen some criticism from [[wine writer]]s and [[viticulturalist]]s who complain about "mono-clonal" viticulture that has the risk of producing wines that are overly similar and dull.<ref name="WSET"/>▼
Grafting is a process in which a new grape vine is produced by making a cut in the [[rootstock]] and then adding scionwood that is cut to fit inside the incision made in the rootstock.<ref>{{Cite web |url=https://articles.extension.org/pages/32923/grafting-grape-vines |title=Grafting Grape Vines - eXtension |website=articles.extension.org |language=en |access-date=2019-04-26 |archive-date=2019-04-22 |archive-url=https://web.archive.org/web/20190422014622/https://articles.extension.org/pages/32923/grafting-grape-vines |url-status=dead }}</ref> This involves removing the canopy and most of the trunk of an existing vine and replacing it with a cutting of a new vine that is sealed by a [[graft union]].
There are two main types of grafting in the relation to the propagation of a grapevine.<ref name="Chip Budding - eXtension">{{Cite web |url=https://articles.extension.org/pages/32924/chip-budding |title=Chip Budding - eXtension |website=articles.extension.org |language=en |access-date=2019-04-26 |archive-date=2019-04-21 |archive-url=https://web.archive.org/web/20190421030754/https://articles.extension.org/pages/32924/chip-budding |url-status=dead }}</ref>
Other criticisms of clonal selection involves the increase disease risk in vineyards lacking genetic diversity among its vines as well as the changing priorities in wine production. While many clones in the mid to late 20th century were isolated, some of the desirable traits exhibited by those clones (such as [[ripe (wine)|early ripening]] or high [[yield (wine)|yield]] potential) may no longer be as desirable today where other traits (such as low yields and drought resistance) may be more prized.<ref name="WSET"/>▼
==== Bench Grafting ====
==References==▼
[[File:Omega-pfropfen.jpg|thumb|243x243px|Omega Graft]]
This process is typically performed in the beginning of a new year in a greenhouse, taking place during the late winter months, to the early spring months. This process is used on younger and smaller vines before the vines are planted in a vineyard. However, the type of cut made on the grape vine determines the classification of the Bench graft. The two techniques to perform a Bench Graft includes the Omega Graft and the Whip Graft.<ref name="Chip Budding - eXtension"/><ref name=":0">{{Cite web |url=https://ptes.org/wp-content/uploads/2017/05/Bench-grafting_Whip-tongue.pdf |title=Bench Grafting Fruit Trees |website=ptes.org}}</ref>
'''The Omega Graft''' is performed by the rootstock and scion being grafted together by the two pieces being cut into shapes that align together.<ref>{{Cite web |url=https://www.bordeaux.com/us/Bordeaux-Magazine-US/Journal/Education/The-Sweet-Science-Behind-Grapevines |title=The Sweet Science Behind Grapevines |date=2017-06-01 |website=Official website Bordeaux.com |language=en-US |access-date=2019-04-26}}</ref>
'''The Whip Graft''' is performed by making an identical small dip at angle into the rootstock and the scion, so they can be adjoined.<ref name=":0" />
==== Field Grafting ====
Field grafting is performed after the vine has been planted in a vineyard and has aged a few years. The objective of using this method is to avoid replanting and a final product of a grapevine with two diversifications. The procedure of field grafting is performed with the vines still planted, by making two inversions in the rootstock of a certain type of grapevines and placing two of the same type of scions that differ from the rootstock into the rootstock. The most common ways to perform field grafting are the Chip Bud method, the T Bud method, the Cleft Graft and the Bark Graft.<ref name="Chip Budding - eXtension"/><ref>{{Cite web |url=http://berrygrape.org/an-illustrated-guide-to-field-grafting-grapevines/ |title=An Illustrated Guide to Field Grafting Grapevines « Northwest Berry & Grape Information Network |language=en-US |access-date=2019-04-26}}</ref>
'''The Chip Bud Method''' is performed shortly after the grape vine is planted, giving the rootstock enough time to become active but the bud of the grape vine is still inactive. It is performed by cutting two small slopes in both sides of the rootstock and cutting a small scion into a small bud and placing the scion bud into the cuts made on the rootstock.<ref>{{Cite web |url=http://irrecenvhort.ifas.ufl.edu/plant-prop-glossary/06-grafting/03-buddingtypes/02-grafting-budchip.html |title=Budding Types, Chip Budding |website=irrecenvhort.ifas.ufl.edu |access-date=2019-04-26 |archive-date=2019-04-24 |archive-url=https://web.archive.org/web/20190424191815/http://irrecenvhort.ifas.ufl.edu/plant-prop-glossary/06-grafting/03-buddingtypes/02-grafting-budchip.html |url-status=dead }}</ref>
'''The T Bud Method''' is performed by making a cutting a T at the bottom of the grapevine that is above the soil. Once the T is cut, the bark surrounding the cut is pulled back and the scion is placed between the two sides that were pulled back.<ref>{{Cite web |url=http://irrecenvhort.ifas.ufl.edu/plant-prop-glossary/06-grafting/03-buddingtypes/06-grafting-budtbud.html |title=Budding Types, T-Budding |website=irrecenvhort.ifas.ufl.edu |access-date=2019-04-26 |archive-date=2019-04-24 |archive-url=https://web.archive.org/web/20190424191817/http://irrecenvhort.ifas.ufl.edu/plant-prop-glossary/06-grafting/03-buddingtypes/06-grafting-budtbud.html |url-status=dead }}</ref>
'''The Chip Graft''' is performed on the branches of a grape vine, when the rootstock is dormant. The method is performed by making a wedge in the rootstock and placing two scions into the wedge. After the Graft starts growing one of the scions is removed, leaving only one to grow.<ref>{{Cite web |url=http://irrecenvhort.ifas.ufl.edu/plant-prop-glossary/06-grafting/02-graftingtypes/06-grafting-cleft.html |title=Grafting Types, Cleft Grafting |website=irrecenvhort.ifas.ufl.edu |access-date=2019-04-26 |archive-date=2019-04-24 |archive-url=https://web.archive.org/web/20190424195845/http://irrecenvhort.ifas.ufl.edu/plant-prop-glossary/06-grafting/02-graftingtypes/06-grafting-cleft.html |url-status=dead }}</ref>
'''The Bark Graft''' is performed by making three incisions on the edge of the grape vine's rootstock, and removing majority of the bark around each of the cuttings, leaving a small amount of bark at the end of the cut and inserting three of the same scions into the incisions, using the remaining piece of the cut bark to cover the end of the scions.<ref>{{Cite web |url=http://irrecenvhort.ifas.ufl.edu/plant-prop-glossary/06-grafting/02-graftingtypes/02-grafting-bark.html |title=Grafting Types, Bark Grafting |website=irrecenvhort.ifas.ufl.edu |access-date=2019-04-26 |archive-date=2019-04-24 |archive-url=https://web.archive.org/web/20190424195845/http://irrecenvhort.ifas.ufl.edu/plant-prop-glossary/06-grafting/02-graftingtypes/02-grafting-bark.html |url-status=dead }}</ref>
=== Layering ===
▲
▲== Clonal versus massal selection ==
▲[[File:Vineyard 1.jpg|left|thumb|One criticism of clonal selection is that the use of only one or two clones greatly diminishes the genetic diversity of a vineyard.]]
▲Each cutting, taken from a mother vine, is a clone of that vine. The way that a vine grower selects these cuttings can be described as either '''clonal''' or '''massal selection'''. In clonal selection,
[[File:Vineyard sign showing Cab Sauv clone.jpg|right|thumb|A vineyard in the Napa Valley showing which particular clone of Cabernet Sauvignon is planted in this block]]
▲Historically, massal selection was the primary means of vineyard propagation, particularly in traditional vineyards where vines are only sporadically replaced, often by layering a cane from a neighboring vine. In the 1950s, the isolation and identification of desirable clones in nurseries and breeding stations lead to an increase in clonal selection with new vineyard plantings seeking out clones from well established vineyards and wine region. This trend towards clonal selection has seen some criticism from [[List of wine professionals|wine
▲Other criticisms of clonal selection
▲== References ==
{{reflist}}
{{Viticulture}}
[[Category:Viticulture
[[Category:Plant reproduction]]
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