D1: The Vine Flashcards
What are the four sections of the vine
- main shoots
- one year old wood
- permanent wood
- roots
What are the 6 components which make up the canopy/major structures of the main shoots?
- stem
- buds
- leaves
- lateral shoots
- tendrils
- inflorescences/grape bunches
Where do the main shoots on the vine grow from?
buds retained from the previous year
What is the stems job?
- what all other structures are attached to
- transports water and solutes to and from different structures
- stores carbs
what are solutes?
- substances that dissolve in a liquid to form a solution e.g. sugars and minerals
what are nodes?
swellings along the stem where other structures attach
what is an internode?
length of stem between nodes
what does ‘lignify’ mean?
- green shoots become woody and rigid
- happens in late summer when leaves fall from vine
- shoots turn brown
- from then on become known as ‘canes’
Buds
- form between the leaf stalk and the stem
- when they mature: contain all structures that become green parts of vine
- two types: COMPOUND and PROMPT
What is a ‘compound bud’
- aka LATENT BUD
- form in one growing season and break open in next growing season to produce main shoots
- within compound bud, get primary, secondary and tertiary buds
- second and tertiary buds only grow if primary bud damaged
What is a ‘prompt bud’
- form and break open in same growing season
- form on main shoot and produce lateral shoots
What is a ‘lateral shoot’
- grow from buds formed in current year (prompt buds)
- have stem, leaves, buds, tendrils, inflorescences
- main function: allow plant to carry on growing if tip of main shoot has been damaged or eaten
- provide additional source of leaves for photosyn
- growing too close to base of main shoot is bad as can impede air flow and shade fruit too much
- can produce inflorescences - depends on grape variety though
what grape variety produces inflorescences on lateral shoots?
Pinot Noir
What is a ‘second crop’
- Where inflorescences are formed on lateral shoots
- become bunches later than those on main shoots and ripen later
- will be higher in acid, lower in alc and have unripe tannins if harvested at same time as normal crop
- can be removed in green harvesting
- if not and are picked during harvest, can have impact on must
What are tendrils
- curl around trellis wires and keep canopy in place
- growers often tie canes and shoots to trellis wires as a precaution as well!
Describe process of photosynthesis
- leaves are main site of photosynthesis in vine
- need sugars from photosyn to support vine growth and metabolism
- stomata open on underside of leaves
- lets water diffuse out and CO2 for PS to enter
- as water diffuses out, transpiration occurs drawing water and nutrients from soil up through vine to leaves
- stomata will partially close if vine is water stressed - limits photosyn by preventing CO2 from entering vine
What are inflorescences
- cluster of flowers on stem which becomes bunch of grapes at fruit set
- usually between 1 and 3 on main shoot
What are bunches
- fertilised inflorescence
- not all flowers in inflorescence will become grapes
- huge variation in grape varieties
EXAMPLE: Pinot noir has tight bunches so makes it more prone to fungal disease due to damage to grape skins
What are grapes made up of?
- pulp
- skin
- seeds
Pulp
- makes up majority of grapes weight and volume
- mostly colourless
- contains:
1. water
2. sugar
3. acid
4. aroma compounds and precursors
What are grapes with red pulp called?
Teinturier varieties
e.g. Alicante Bouschet
Grape Skin
- contains:
1. high concentration of aroma compounds and precursors
2. tannins
3. colour compounds
Grape Seeds
- Contains:
1. oils
2. tannins
3. embryon
What is the powdery, waxy coating on a grape called?
Bloom
- covers surface of grape
How is a grape attached to the vine?
- by a stem
- stem contains tannins
What is ‘one year old wood’?
- main shoots from last growing season which were kept at pruning
- OYO wood supports compound buds
- will either be called ‘cane’ or ‘spur’ depending on pruning techniques
What is ‘permanent wood’?
- woody parts of wine older than one year
- includes trunk
- may have one or more horizontal arms of perm wood called ‘cordons’
What is the role of the trunk and cordons?
- provide support for other parts of vine
- transport water and solutes to and from diff parts of vine
- store carbs
What is the role of the roots?
- anchor vine
- imp for uptake of water and nutrients
- store carbs
- produce hormones which are imp for vine growth and grape ripening
- usually found in top 50cm of soil
- can go deeper but depends on soil, irrigation, cultivation etc
Where are water and nutrients absorbed?
root tips where roots are actively growing
How are vines propagated?
by layerings or cuttings
- create genetically identical plants to parent plant
What is a cutting?
A selection of vine shoot that is planed and then grows as a new plant
- most common technique as can take many cuttings and can propogate all at same time
- can use rootstocks so can be easily grafted onto vine cutting before being planted
- nurseries can treat cuttings to avoid spread of disease