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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 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 that has been selected by either 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 of an existing vine into the ground next to the vine and severing the connection when the new vine develops its own root system.〔Wine & Spirits Education Trust ''"Wine and Spirits: Understanding Wine Quality"'' pgs 2-5, Second Revised Edition (2012), London, ISBN 9781905819157〕 In commercial viticulture, grapevines are rarely propagated from seedlings 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 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 grape Baco blanc which was propagated from the ''vinifera'' grape Folle blanche and the ''Vitis labrusca'' variety Noah.〔 ==Terminology== In viticulture, a clone is single vine that has been selected from 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, 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 may be slight mutations to differentiate the various clones, all clones are considered genetically part of the same variety (i.e. Sangiovese or Pinot noir).〔J. Robinson (ed) ''"The Oxford Companion to Wine"'' Third Edition pgs 183-184 Oxford University Press 2006 ISBN 0-19-860990-6〕 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.〔 A crossing is a new grape variety that was created by the cross pollination of two different varieties of the same species. Syrah is a crossing of two French ''Vitis vinifera'' species, Dureza from the Ardèche and Mondeuse blanche from Savoie.〔J. Robinson, J. Harding and J. Vouillamoz ''Wine Grapes - A complete guide to 1,368 vine varieties, including their origins and flavours'' pgs 316, 528 & 1023, Allen Lane 2012 ISBN 978-1-846-14446-2〕 Theoretically every seedling (also known as a Selfling), even if its pollinated by a member of the same grape variety (i.e. such as two Merlot vines), is a crossing as any vine that results from the seed being planted will be a different grape variety distinct from either parent.〔 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 winemaking, 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 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 rootstocks to ''vinifera'' varieties was found. Eventually the use of hybrids in wine production declined with their use formally outlawed by European wine laws in the 1950s.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Propagation of grapevines」の詳細全文を読む スポンサード リンク
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