Ch. 0 – Viticulture Flashcards
Most common species of vine
Vitis Vinifera
Vitis Lambrusca
Vitis Riparia
Vitis Berlandieri
Vitis Rupestris
Name parts of vine
Tendril
Lateral Shot
Inflorescence
Leaf
Compound bud
Main Shoot
Cane
What is the lenght of stem between nods called?
Internod
What does stem transport?
Water and solutes (substances dissolved in liquid - minerals and sugars)
Explain compound bud
Also called latent bud
Form in one growing season and break open in the next one
Primary bud opens first (followed by secondary or tertiary if necessary)
Explain prompt bud
Form and break in the same season and produce lateral shoots
Main functions of lateral shoots
Back up if main shoot is damaged.
Additional source of leaves for photosythesis
May have inflorescences (second crop) those ripen later or may be removed.
Explain photosythesis
Stomata (pores) open on underside of the leaves letting water diffuse out and carbon dioxide to enter.
Transpiration - transport of water from soil and roots back to leaves
Stomata closes if vine has water stress
Describe composition of grape berry
Pulp - water, sugars, acids and some aroma compounds and aroma precursors
Skin - high concentration of aroma compounds and precursors, tannins and colour compounds
Seeds - oils, tannins and embryo for new plant
Bloom - waxy coating of skin
Stem
2 kinds of vine propagations - explain
Cuttings - section of vine that is planted and grows as new plant. Can be grafted on selected rootstock and treated in nursery against deseases.
Layering - Establish neighbouring vine’s shoot is buried in the ground. New vine grows on its own roots.
Both methods are geneticaly identical to the parent (vines from seeds are not)
Explain clonal selection
Vines with favourable characteristics are propagated in nurseries by cuttings.
Explain mass selection (Selection Massale)
Grower takes cuttings from best performing vines in his vineyard and propagate them by cuttings (may graft them on rootstock)
Own unique planting material
Increases diversity
Costly in terms of time and labour
Possible spread of diseases (from parent)
New vines from seeds
Cross X Hybrid
Cross - parents from the same species
Hybrid - parents from different species
Dormancy (temperatures, hazards, management)
Below 10 degrees
Below -15 degrees hazard of damage or killing vine
Unusual warm can trigger budburst
Winter pruning
Budburst (temperatures, factors, hazards)
Temperature above 10 degrees
Continental climate advantageous with large winter/summer difference - uniform budburst
Maritime climate caìn be less synchronized
Other factors: temperature of soil (sand warms up quickly) and grape variety
Hazard of frost and cold days
Reasons of low carbohydrate levels in roots from previous season
Excessive leaf removal
Water stress
Mildew infections
High crop loads
Shoot and leaf growth stage (needs)
Stored carbohydrates from previous season
Warmth, sunshine, nutrients and water
Petioles
Base of leaf stalks where new buds develop
Fruitfullness
Number of inflorescenses
Describe pollination
Pollen-lade stamens (consisting of anther and filament) are exposed.
The pollen grains are shed and land on the moistened stigma surface
They germinate, each producing pollen tube
Pollen tubes penetrate stigma and then the ovule in the ovary.
Pollen tube delivers the sperm cells which fertilizes the egg in the ovule
Ovule forms up to 4 seeds
The wall of ovary enlarges to form the skin and pulp of the grape
Conditions for successful flowering
(timing, temperatures
8 weeks from budburst (temperature dependent)
min 17 degrees
sunlight, nutrients, water
adverse conditions: rain, clouds, cold temperatures
Pollen germination needs temperature of 26-32 degrees
Coulure
Grape bunch in which fruit set has failed for high proportion of flowers
Imbalance of carbohydrate levels (low rates of photosythesis - cold, cloudy, hot weather, water stress OR vigorous shoot growth)
Grenache, Malbec, Merlot, Cabernet Sauvignon are the most susceptible
Millerandage
High proportion of seedless grapes in bunch - smaller grapes
lower volume of wine or unequal ripeness
Usually from cold, wet, windy weather at pollination and fruit set
Chardonnay, Merlot are susceptible
Methoxypyrazines
contribute to herbaceous aromas/flavours
Sauvignon Blanc, Cabernet Sauvignon, Cabernet Franc