PIWI: Difference between revisions
CodexWarrior (talk | contribs) m CodexWarrior: canonicalise ISBN refs |
|||
| (2 intermediate revisions by one other user not shown) | |||
| Line 1: | Line 1: | ||
'''PIWI''' refers to a group of [[grape varieties]] bred for resistance to fungal diseases, particularly [[downy mildew]] and [[powdery mildew]], developed primarily to reduce chemical inputs in [[viticulture]] while maintaining suitability for quality wine production.<ref>Robinson | '''PIWI''' refers to a group of [[grape varieties]] bred for resistance to fungal diseases, particularly [[downy mildew]] and [[powdery mildew]], developed primarily to reduce chemical inputs in [[viticulture]] while maintaining suitability for quality wine production.<ref>Jancis Robinson, ''Oxford Companion to Wine'', Oxford University Press, 17 Sept. 2015. ISBN 9780198705383.</ref> The term originates from the German ''pilzwiderstandsfähig'' (“fungus-resistant”) but is now used internationally in professional, regulatory and academic wine contexts. | ||
== Origin and definition == | == Origin and definition == | ||
PIWI varieties are the result of targeted breeding programmes that combine resistance traits from non-[[Vitis vinifera]] species with vinifera parentage, followed by successive backcrossing to recover wine-quality characteristics.<ref>Becker, ''PIWI Grape Varieties'', Becker Verlag, 2014, ISBN 978-3897983863.</ref> Unlike early interspecific hybrids developed in the 19th and early 20th centuries, modern PIWI cultivars are selected specifically for both disease resistance and sensory suitability in wine. | [[[[PIWI]] varieties]] are the result of targeted breeding programmes that combine resistance traits from non-[[Vitis vinifera]] species with vinifera parentage, followed by successive backcrossing to recover wine-quality characteristics.<ref>Becker, ''PIWI Grape Varieties'', Becker Verlag, 2014, ISBN 978-3897983863.</ref> Unlike early interspecific hybrids developed in the 19th and early 20th centuries, modern [[PIWI]] cultivars are selected specifically for both disease resistance and sensory suitability in wine. | ||
The term is descriptive rather than genetic, referring to functional resistance rather than a strict taxonomic category.<ref>Robinson, Harding & | The term is descriptive rather than genetic, referring to functional resistance rather than a strict taxonomic category.<ref>Jancis Robinson, Jose Vouillamoz, Julia Harding, & 0 more, ''Wine Grapes: A Complete Guide to 1,368 Vine Varieties, Including Their Origins and Flavours'', Ecco, 1 Nov. 2012. ISBN 9780062206367.</ref> | ||
== Breeding background == | == Breeding background == | ||
Most PIWI varieties derive resistance from American or Asian grape species that co-evolved with fungal pathogens, particularly ''Plasmopara viticola'' and ''Erysiphe necator''.<ref>Becker, ''PIWI Grape Varieties'', Becker Verlag, 2014, ISBN 978-3897983863.</ref> These resistance loci are introgressed into vinifera backgrounds through controlled crossing and long-term selection. | Most [[PIWI varieties]] derive resistance from American or Asian grape species that co-evolved with fungal pathogens, particularly ''Plasmopara viticola'' and ''Erysiphe necator''.<ref>Becker, ''PIWI Grape Varieties'', Becker Verlag, 2014, ISBN 978-3897983863.</ref> These resistance loci are introgressed into vinifera backgrounds through controlled crossing and long-term selection. | ||
Modern breeding programmes focus on [[polygenic resistance]] to reduce the risk of pathogen adaptation, alongside traits such as early ripening, balanced acidity and moderate sugar accumulation.<ref>Robinson, Harding & | Modern breeding programmes focus on [[polygenic resistance]] to reduce the risk of pathogen adaptation, alongside traits such as early ripening, balanced acidity and moderate sugar accumulation.<ref>Jancis Robinson, Jose Vouillamoz, Julia Harding, & 0 more, ''Wine Grapes: A Complete Guide to 1,368 Vine Varieties, Including Their Origins and Flavours'', Ecco, 1 Nov. 2012. ISBN 9780062206367.</ref> | ||
== Viticultural rationale == | == Viticultural rationale == | ||
The primary motivation for PIWI cultivation is the reduction of fungicide use, particularly in cool, humid climates where disease pressure is high.<ref>OIV, “Hybrid and resistant varieties”.</ref> Resistant varieties can significantly lower the number of vineyard spray applications required per season, supporting environmental sustainability and economic viability. | The primary motivation for PIWI cultivation is the reduction of fungicide use, particularly in cool, humid climates where disease pressure is high.<ref>OIV, “Hybrid and resistant varieties”.</ref> Resistant varieties can significantly lower the number of vineyard spray applications required per season, supporting environmental sustainability and economic viability. | ||
PIWI grapes are therefore closely associated with [[organic viticulture]], low-intervention farming and regions facing increasing regulatory pressure on chemical inputs.<ref>Robinson | PIWI grapes are therefore closely associated with [[organic viticulture]], low-intervention farming and regions facing increasing regulatory pressure on chemical inputs.<ref>Jancis Robinson, ''Oxford Companion to Wine'', Oxford University Press, 17 Sept. 2015. ISBN 9780198705383.</ref> | ||
== Relationship to hybrid grapes == | == Relationship to hybrid grapes == | ||
PIWI varieties are sometimes described as hybrids, but the terms are not synonymous. While PIWI grapes are technically of hybrid origin, the designation emphasises disease resistance rather than genetic composition.<ref>Robinson, Harding & | PIWI varieties are sometimes described as hybrids, but the terms are not synonymous. While PIWI grapes are technically of hybrid origin, the designation emphasises disease resistance rather than genetic composition.<ref>Jancis Robinson, Jose Vouillamoz, Julia Harding, & 0 more, ''Wine Grapes: A Complete Guide to 1,368 Vine Varieties, Including Their Origins and Flavours'', Ecco, 1 Nov. 2012. ISBN 9780062206367.</ref> | ||
Historically, the term [[hybrid grape]] is associated with earlier interspecific varieties often criticised for atypical flavour profiles. Modern PIWI cultivars are the product of extensive backcrossing and quality-focused selection, and many are indistinguishable from vinifera wines in blind tasting. | Historically, the term [[hybrid grape]] is associated with earlier interspecific varieties often criticised for atypical flavour profiles. Modern PIWI cultivars are the product of extensive backcrossing and quality-focused selection, and many are indistinguishable from vinifera wines in blind tasting. | ||
| Line 24: | Line 24: | ||
PIWI varieties are used to produce a wide range of wine styles, including dry [[white wine]], [[red wine]] and [[sparkling wine]]. Sensory profiles vary by cultivar, but modern examples aim for neutrality, freshness and varietal clarity rather than pronounced hybrid character.<ref>Becker, ''PIWI Grape Varieties'', Becker Verlag, 2014, ISBN 978-3897983863.</ref> | PIWI varieties are used to produce a wide range of wine styles, including dry [[white wine]], [[red wine]] and [[sparkling wine]]. Sensory profiles vary by cultivar, but modern examples aim for neutrality, freshness and varietal clarity rather than pronounced hybrid character.<ref>Becker, ''PIWI Grape Varieties'', Becker Verlag, 2014, ISBN 978-3897983863.</ref> | ||
Quality perception has improved significantly since the early 2000s, with PIWI wines increasingly accepted in professional tastings and competitions.<ref>Robinson | Quality perception has improved significantly since the early 2000s, with PIWI wines increasingly accepted in professional tastings and competitions.<ref>Jancis Robinson, ''Oxford Companion to Wine'', Oxford University Press, 17 Sept. 2015. ISBN 9780198705383.</ref> | ||
== Distribution and regulation == | == Distribution and regulation == | ||