Unit 1 Viticulture- The Vine Flashcards
(53 cards)
What is the function of the roots?
Absorb water and nutrients, store carbohydrates to allow winter survival, anchor the vine
What part of the vine stores CHO?
Trunk and arms
What is the difference between prompt and dormant buds?
Prompt buds break in the same year they are formed, and dormant buds break the following spring
How can you determine the nutrient requirements of a vine?
Petiole (leaf stalk) analysis
What are tendrils?
Tendrils search out trellis wires and wind around them, enabling shoots to stay upright
What natural factor can result in low fruit set?
Too much rain or wind during flowering which can blow away the pollen
What is wood ripening?
When CHO are stored in canes to provide energy for the following year, after version and before ripening
What is the result of shoots being destroyed by spring frost at bud burst?
Secondary buds will grow but are much less fruitful
What is coulure ?
Failure of fruit set
How are vines treated in the first two to three years of growth?
The vine grows its trunk and permanent wood, the vine must focus on vegetative growth, so bunches are usually removed, the root system is established
Why can the first few crops from a vine be very high quality?
The trunk and arms are thin, the CHO reserves are low, which limits the vigour of shoot growth. This results in a very good fruit to leaf balance and well exposed fruit.
What happens to the vine between 7 and 20 years?
- Permanent wood thickens (but less and less)
- Canopy needs to be managed to avoid excessive shading
- Potential yields are the highest
- Quality drops after the first few years
What happens to the vine after 20 years?
- Declining vigor
- Fruit to leaf balance is restored to early year levels but yield declines
- The grower may replant, or may be used as old vines
What are the 4 main criteria to consider when selecting vines?
- Adaptation to climate
- Resistance to disease
- Adaptation to soil conditions
- Economic characteristics (High yield, mechanization high quality)
Where are interspecific hybrids forbidden?
Most ofEurope
What are interspecific hybrid varietals?
Crosses of one vinifera varietal with another
What are some examples of interspecific hybrid varietals?
Muller-Thurgau, Alicante Bouschet
What is mass selection and why is it no longer used?
Passing through vineyard before harvest and marking the best plants from which to take cuttings, not done due to necessity of grafting instead of taking cuttings and success of cloning
What is cloning?
Plants originating from a single parent propagated vegetatively by cuttings and therefore genetically identical
On what was clonal selection first carried out on?
Silvaner in Germany
What is the difference between clonal selection and mass selection?
With clonal selection only a handful (<10) of plants are selected and propagated extensively, whereas mass selection results in poly-clonal populations
What 7 factors are used to select clones?
- Yield (fertility, berry size)
- Sugar concentration
- Phenolic constituents
- Resistance to disease and draught
- Freedom of viral infection
- Ease of grafting
- Cost
What are the 4 disadvantages of clonal selection?
- Disease spreads easily
- Clones are very specialized to certain regions/styles of wine
- Leads to increase in yield/overproduction
- Led to reduction in vine genetic resources
Are GM vines available for use in commercial vineyards?
No
