Ch. 3 Grape Varieties Flashcards
- State the differences between Vitis vinifera and other vine species. - Discuss hybrids, crossings, and clones. - Describe the primary characteristics of the classic intentional white grape varieties. - Describe the primary characteristics of the classic international red grape varieties.
What genus to grapes belong to?
Vitis
What species of grape is used on a widespread basis in commercial winemaking?
Vitis Vinifera
Where did vinifera vines develop?
Caucasus Mountains region
Where are the Caucasus Mountains?
between Europe and Asia
How did differences develop among grapewines?
- the habitat of vinifera vines expanded
- natural evolution
- encouragement given to certain vines over others by early grape growers
True or False:
Eventually, the differences between vinifera vines become distinct enough to that they could be identified as subspecies.
True
What is another term for vine subspecies?
grape varieties
How many grape varieties (subspecies) are there.
thousands
Name an example of a grape variety (subspecies).
- Sauvignon Blanc
- Merlot
True or false:
Vinifera is the only grape species in North America.
False. Vitis labrusca is the second most important grape species.
What is vitis labrusca?
The second most important grape species because it makes table grapes for fresh consumption or unfermented grape juice.
What is the second most important grape species in North America?
Vitis Labrusca
What do vitis labrusca grapes taste like?
Sweet, flavorful, high in acidity
Name a subspecies of vitis labrusca.
Concord grape
What is the term given to the flavor component vitis labrusca grapes give to wine?
foxy
True or false:
North American vines have a natural resistance to phylloxera.
True
What is phylloxera?
An aphid-like insect that ravaged European vineyards in the nineteenth century.
What is a scion?
The vinifera part of the vine
How can winemakers create a phylloxera-resistant plant?
By grafting a scion onto the trunk, or rootstock of a North American vine
Which North American wine species are used for grafting phylloxera-resistant plants?
vitis labrusca
vitis riparia
vitis aestivalis
vitis rupestris
What is a species?
A grouping of grapevines that are genetically similar, have broad characteristics in common, and can produce viable offspring through sexual reproduction.
What are examples of grape species?
vitis vinifera
vitis labrusca
What is a variety?
A named type of grape vine with recognizable characteristics; more of less synonymous with subspecies
What is a clone?
A clone is a grapevine grown by rooting or grafting a cutting from another vine, which is therefore genetically identical to the original plant
OR
A grape variety that has mutated to be slightly different from its parent.
True or false:
Nearly all commercial grape varieties are propagated by asexual means.
True
True or false:
Clones are perfect copies of or copies that slightly differ from the parent grape.
True
How does genetic variation occur in grapes?
When aesxually reproduced grapevines are planted in new surrounds and slight genetic variations occur as the plant modifies itself to adapt to its new conditions.
When is a new vine determined to be a new clone?
When it shows a consistent distinction from its parent
True or false:
New clones are not given new names.
False. New clones generally have a new name or a number assigned to the grape.
What is a mutation?
A mutation is a genetic change; a natural but random alteration to the DNA of a grapevine that results in traits unlike those of the plant’s parents or clone source.
How can mutations occur?
A vine develops different characteristics from its parent (or fellow clones) through the imperfect reproduction of cells as it grows.
True or false:
Mutations cannot lead to new types of grapes varieties.
False. Natural, slow development can lead to new types of grapes that show significant differences from its ancestors and can be determined a separate grape variety.
What is a cross?
The offspring of sexual reproduction between different subspecies within the same species.
What are two examples of Pinot Noir mutations?
- Pinot Blanc
2. Pinot Gris
What is an example of a crossing?
Cabernet Sauvignon (cross between Cabernet Franc and Sauvignon Blanc)
What is a hybrid?
The result of sexual reproduction between two closely related but different species.
Why have hybrids often been developed?
An attempt to create a grape resistant to challenges such as mildew, phylloxera, cold weather, humidity, etc.
Why are hybrids not universally accepted for use in commercial wine?
They struggle to develop adequate levels of tannin and can be exceedingly acidic.
