1 Flashcards
Reproduction
Pollination
Anthers (testes) mature and release pollen ( sperm) >
Transported by wind >
Lands on stigmas of other grape varieties
Grapes
Reproductive organs in flowers
Wind pollinated, animal dispersed
Small flowers. Brightly colored fruit
Almost all flowers are hemaphrodite
Have genetic material from both parentsFertilization
Pollen transfers genetic material via tube in ovary >
Combines with genetic material contained in ovules (eggs)>
Fertilized ovules develop into seeds
Ovary develops into surrounding flesh and skin of grape
Grape characteristics important to winemaker
Yields Hardiness Disease resistance Fruit character Levels of tannin Acidity Sugar
Hybrids
Made by scientists or nursery 2 separate species Artificial Get good characteristics from both species eg frost humidity resistant Forbidden in eu Used as rootstock Europe - v.vinifera America - v lambrusca, riparia, rupestris Asiatic - v. Amurensis
Crossings
Reproduction naturally
Parents of diff variety of same species
May not keep characteristics from parents
After creation only propagation is through cutting
Specialists - geisenheim, uc Davis
Asexual propagation
Cuttings taken from individual vines that show desirable traits
Ensures same characteristics as parent vines >
Seeds may contain diff genetic material
How classic varieties originally developed
Clones
Growing a plant from a cutting
Genetic instructions copied for each new cell
Accurate but mutations can happen
With variety diff clones can have better or worse traits eg high yields, disease resistance
Vine grower selects clones better suited for breeding
Pinot blanc and Pinot Gris are clones of Pinot noir
How phylloxera kills vines
Wounds made by Ouse feeding on vines allow bacteria to enter>
Decay>
Disease>
Death
How is american rootstock resistant to phylloxera
For. Protective layers under feeding wounds >
Prevents further damage
Some areas not affected by phylloxera today
Chile S.aus Arg Hungary Some areas Due to geographic isolation and quarantine procedures Sandy soils restrict life cycle
Another pest deterred by grafting
Nematodes
From drip irrigation
Head grafting
In nw vyds Produces vines quickly to meet consumer needs Top of existing vine is removed Cutting is grafted on Will produce fruit for next vintAge
Grafting 2 parts of the vine
American rootstock
European scion
