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What is the correct name of Phylloxera vastatrix (the devastator)?
Dactylosphaera vitifoliae
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Describe 3 defense mechanisms of American vines to Phylloxera
- Roots mend the wounds caused by the insect, sealing them from invasion by bacteria or fungi
- Sap clogs the feeding apparatus of the insect
- Something in the roots causes juveniles to die
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On what part of the vine does Phylloxera breed?
- On American vines, the leaves
- On European vines, the roots
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Name 4 reasons why Phylloxera is so challenging to deal with
- Adaptability to its surroundings (e.g., Biotype B variant of Phylloxera resistant to AXR1 rootstock)
- Ability to differentiate between American, European, and hybrid species
- Different behavior in sandy, clay, or chalk-rich soils
- Dislike of very hot and wet soils
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Phylloxera is parthenogenetic. What does that mean?
It is able to lay fertile eggs without a male
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Almost all Phylloxera eggs laid hatch into females. T or F?
True
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How many generations can a female Phylloxera lay in a single season?
7
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What are galls and where are they seen?
Galls contain unhatched Phylloxera eggs. The appear on leaves and roots.
Note: On American vines, these reddish/brown lumps are on the leaves. The eggs hatch into aphids; some turn into crawlers and creep down to find roots. Crawlers inject their saliva into roots causing root galls.
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How does phylloxera spread?
- Spread below ground from root to root and from vine to vine by crawlers.
- Fertile adults emerge from the soil and crawl across the ground.
- In warm climates, a winged form exists which can fly about 100m.
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The female offspring of the winged form of Phylloxera lays winter eggs. What can it hatch into?
Fundatrix; the mother ("queen bee") of a new generation in a new location.
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When and where did Thomas Jefferson try to establish vinifera vineyards?
In 1773 he hired Italian grower Filippo Mazzei to establish a 400 acre vineyard adjoining Monticello in Virginia. However, it succumbed to Phylloxera or Oidium (Powerdery Mildew).
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When was Phylloxera first seen?
- 1861: Pujaut, Rhone village (planted 1861, attacked 1863, spread 1865)
- 1863: Hammersmith, West London
- 1860s: California
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How did Phylloxera spread in Europe?
- 1872: Douro in Portugal
- 1874: parts of Spain
- 1875: first sighting in southern Germany (grubbing with compensation kept under control until WWII).
- 1879: Italy
- 1890: Champagne (by this time, grafted vines were established in the south and west of France)
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Did the French warn California that AXR1 was not resistant to Phylloxera?
Yes; contrary to U.C. Davis advice. By 1980s, such vineyards were succumbing to Phylloxera.
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What is the correct name of Powdery Mildew (initially called Oidium tuckeri)?
Uncinula necator
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How can Powdery Mildew be treated?
Spraying/dusting with sulphur
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Where was Powdery Mildew found in 1845?
A greenhouse in Margate, Kent, England
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Name some vineyards not planted with grafted vines
- Chile: Andes barrier
- Australia: quarantine (e.g., pressure-wash equipment)
- Argentina: flood irrigation
- Ernst Loosen: Mosel slate-covered slopes are layered, not re-planted
- Vin de Sables: In sandy soils of the Rhone
- Quina do Noval: Nacional vintage port
- Bolinger: Vieilles Vignes Francaises are planted en foule
- DRC: La Romanee-Conti and Richebourg (grubbed up in 1945; replanted in 1947 with a selection massale (multi-clone) taken from the old vines.
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Define "en foule" ("in a crowd")
System of random planting where replacement vines are layered rather than re-planted.
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Name a recent development in Phylloxera control
Use of a soil fungus (Metarhizium anisopliae) which infect the pest with a disease that kills it
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Is there evidence that the flavor of wine produced from a vine attached to non-vinifera root stock is tainted in any way?
No
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What was a good yield of a top Bordeaux estate before and after the Phylloxera crisis?
- Before: 10-15 hl/ha
- After: 60-75 hl/ha
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Why has yield increased after the Phylloxera crisis?
A grafted vine may be more vigorous, have a deeper root system, and denser canopy.
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Name 8 reasons to use rootstock
- anti-Phylloxera: V. riparia, V. rupestris, V. berlandieri best; Borner (riparia X cinerea) best, AXR1 (aka ARG1) (vinifera X rupestris) failure.
- lime-induced chlorosis: V. berlandieri with high active CaCO3 (calcium carbonate) content
- nematode resistance: V. champini and V. longii best (e.g., Dog Ridge, Freedom Harmony, Ramsey); crosses with V. vinifera worst
- drought resistance: V. berlandieri X V. rupestris roots dig deep so best; V. riparia and hybrids worst
- Salt tolerance: V. berlandieri, V. champini (Ramsey) and viniferas help
- Promote growth: V. rupestris (e.g., Rupestris St. George, 99R, 110R)
- Vigor-reducing: V. riparia (e.g., Riparia Gloire de Montepellier (RGM), 420A, 41B, 161-49, 101-14)
- Advance maturity: in cooler regions
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How does root stock affect the characteristics of the same cultivar and clone of a variety, grown on the same site?
- Time of bud-burst, veraison, harvest
- yeild
- pH
- Sugar and acidity
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Once selected, can a rootstock be changed?
No
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