2. The Vine Growth Cycle Flashcards
What are terpenes?
Aroma compounds that give floral and citrus aromas (ex. “grapey” aromas found in Muscat
What happens during grape berry formation? (6)
- Hard green grapes grow in size
- Tartaric and malic acids accumulate
- Tannins develop (very bitter)
- Some aroma compounds + precursors develop
- Sugar levels are low
- Water flow into grape is high
What is phloem?
Type of transport tissue that transfers sugars from leaves to other parts of vine
What is flowering? What are conditions for it to be successful? (1)
Opening of individual flowers within a florescence (ideally within 8 weeks of budburst.) Warm temperatures (min of 17)
What is millerandage? What causes it?
Condition of grape bunch where there is a high proportion of seedless grapes (can still ripen but are small.)
Cold, wet and windy weather at fruit set and pollination
What’s a xylem?
Type of transport tissue that transfers water and some nutrients from roots to other parts of vine
What factors influence timing of budburst? (4)
Air temperature (above 10C) Soil temperature (higher = earlier budburst) Grape variety (early budding vs. late budding) Human factors (ex. winter pruning)
What are the 7 stages of vine growth cycle?
1) Dormancy (Nov-Mar)
2) Budburst (Mar-Apr)
3) Shoot and Leaf Growth (Mar-July)
4) Flowering and Fruit Set (May-June)
5) Grape Development (June-Oct)
6) Harvest (Aug-Oct)
7) Leaf Fall and Dormancy (Nov-Dec)
What happens during veraison? (3)
- Grape growth slows down
- Grape walls become more stretchy and supple
- Change in colour
What happens during ripening?
- Sugar and water levels accumulate
- Acid levels fall
- Tannins, colour and aroma compounds develop
What happens during dormancy?
Vine survives off carbs in roots/trunk/branches
Winter pruning is carried out
What factors will influence length of ripening stage? (4)
Grape variety (PN and Chard are early, Grenache is late)
Climatic conditions
Management of vine/vineyard
Time of harvest
What temperature is it too cold for vines to grow? What temperature can cause vines to die?
Below 10 degrees Celsius is too cold to grow.
-15 degrees Celsius can cause vines to die.
What is fruit set?
The transition from flower to grape
What is coulure? What causes it? (2)
Condition of grape bunch which fruit set has failed for a high proportion of flowers.
Imbalance of carb levels and vigorous shoot growth that diverts carbs
