2. The Vine Growth Cycle Flashcards
What factors are important for the vine to produce grapes suitable for making wine?
heat, sunlight, water, nutrients, and the timings of these key resources within the growth cycle.
Name the stages of a vine growth cycle. Put them into appropriate order.
- Dormancy (November–March in the Northern Hemisphere, May–September in the Southern Hemisphere)
- Budburst
March–April in the Northern Hemisphere, September–October in the Southern Hemisphere - Shoot and Leaf Growth
March–July in the Northern Hemisphere, September–January in the Southern Hemisphere - Flowering and Fruit Set
May–June in the Northern Hemisphere, November–December in the Southern Hemisphere - Grape Development
June–October in the Northern Hemisphere, December–April in the Southern Hemisphere
When does winter dormancy start and end?
With leaf fall in the autumn (November) and ends with budburst in the spring (March).
What average air temperatures are too cold for the vine to grow?
Below 10°C
How does the vine support its growth when it cannot photosynthesise?
By using stores of carbohydrates, mostly starch.
Where are the nutrients accumulated during the previous growing season?
In the roots, trunk and branches.
Define bud burst.
the process, when buds swell and open, and green shoots start to emerge..
What does the timing of budburst depend on?
AIR TEMPERATURE
SOIL TEMPERATURE
GRAPE VARIETY
HUMAN FACTORS
What average air temperature is needed for budburst?
10°C
Why can regions that have MARKED differences in temperature between the various seasons be ADVANTAGEOUS for successful budburst?
rapidly increasing temperatures in the spring =>
budburst can be relatively uniform =>
the homogeneity of later stages in the growing season =>
a crop of grapes with even ripeness.
In what regions can bud burst be less synchronized?
In regions where there is often less contrast between winter and spring temperatures (for example, maritime climates.
Why can DRY, free-draining soils (sandy soils) compared to water-storing soils (clay-rich soils) be ADVANTAGEOUS in cool climates for bud burst and ripening?
They tend to warm up more quickly than water-storing soils. Higher soil temperatures around the roots => earlier budburst.
An early start to the growing season=> better ripening.
Define early budding grape varieties.
Varieties that require relatively LOW temperatures at budburst.
Give examples of EARLY budding grape varieties.
Chardonnay, Pinot Noir, Merlot and Grenache.
Define late budding grape varieties.
Grape varieties that require HIGHER temperatures at budburst.
Give examples of LATE budding grape varieties.
Sauvignon Blanc, Cabernet Sauvignon and Syrah.
What viticultural practices can delay budburst?
winter pruning late in the dormant period
Define inflorescences.
a cluster of flowers on a stem.
What determines the vigour of the vine?
The rate of shoot growth.
When does the fastest rate of growth occur?
Between budburst and flowering.
Is the speed of shoot growth the same for all vines and in all parts of the vine?
No. It can vary between vines and within different parts of the same vine.
How is the initial shoot growth supported?
By carbohydrates stored in the roots, trunk and branches.
What can decrease the level of carbohydrates storage?
Excessive leaf removal,
water stress,
mildew infections,
high crop loads in the previous growing season.
What do leaves need for successful photosynthesis and growth?
Warmth and sunlight.
Where to is most of the vine’s energy directed until flowering starts?
Towards shoot growth.
What nutrients are needed for vine growth?
Nitrogen (N),
potassium (K),
phosphorus (P).
What can limit photosynthesis and shoot growth?
- water stress
- dry soils around the roots
- low carbohydrate levels (caused by conditions in the previous growing season)
What are the effects of stunted (slowed) shoot growth?
small, weak shoots =>
reduction in leaf number or smaller leaves =>
inflorescences that do not flower properly =>
grape bunches that do not ripen fully =>
poor quality and lower yields.
What does the vine need during shoot and leaves growth?
- Stored Carbohydrates
- Warmth, sunlight, nutrients and water
Define bud fruitfulness.
the number of inflorescences that will develop from a bud.
What can limit bud fruitfulness?
Shading of compound buds,
low temperatures (under 25°C),
water stress,
nutrient deficiency.
Define flowering.
the opening of the individual flowers within an inflorescence.
Name the parts of the vine flower.
Stamen — тычинка (Anther — пыльник + Filament — волосок, тычиночная нить) Pollen — пыльца Stigma — рыльце пестика Pollen tube - пыльцевая трубка Ovule — семязачаток, семяпочка; яйцева клетка Egg Ovary — маточник, завязь; яичник Germination — проращивание, всхожесть Penetrate - проникать
Describe the initial stage of flowering.
The pollen-laden stamens (consisting of an anther and filament) are exposed.
Describe the pollination.
The pollen grains are shed and land on the moistened stigma surface.
How is ovule fertilized? Describe a grape berry formation.
On the moistened stigma surface pollen grains germinate, with each pollen grain producing a pollen tube.
These pollen tubes penetrate the stigma and then the ovule (the female reproductive cells) in the ovary.
The pollen tube delivers the sperm cells, which fertilise the eggs in the ovule. This leads to the formation of a grape berry.
How are seeds formed?
The fertilised ovules form seeds.
