The vine: The anatomy of the vine 1

Question 1

All vines have a similar structure. this structure can be divided into four sections:

Answer 1

1) Main shoots
2) One Year Old Wood
3) Permanent woods
4) Roots

Question 2

What are the major structures of the main shoots, and how are they collectively called ?

Answer 2

The main shoots and all their major structures:

• stem
• buds
• leaves
• lateral shoots
• tendrils
• inflorescences/ grape bunches

These are collectively called the canopy

Question 3

From where does the main shoot comes ?

Answer 3

The main shoots on the vine grow in spring from buds retained from the previous year.

Question 4

What is the essence of the stem ?

Answer 4

The stem is the structure to which all the other structures are attached.

— it transports water and solutes (opgeloste stoffen) to and from the different structures

—- The stem is also a store (opslagruimte) of carbohydrates

Question 5

what are solutes ?

Answer 5

They are a substance (stof) that dissolve in a liquid to form a solution and in this instance includes sugars and minerals

Question 6

What are nodes ?

Answer 6

Are the little swellings along the stem, where the other structures are attached

— the lengths of stem in between the nodes are called inernodes.

Question 7

What happens with the vine in late summer ?

Answer 7

1) the leaves fall from the vine
2) the green shoots ignify (become woody and rigid (stijf) and turns brown
3) from this point they are called canes.
4) during the winter the vine will be pruned (cane 8-20 buds, spur 2-3 buds)

Question 8

What and where are buds ?

Answer 8

buds form between the leaf stalk (petiole) and the stem.

As they mature, they contain all the structures in miniature that will become green parts of the vine, including the stem, buds, tendrils, leaves and often inflorescences

Question 9

You have 2 types of buds:

Answer 9

1) Compound buds (latent buds):
- form in one growing season and break open in the next growing season (provided they are retained during winter pruning)
- - they produce the main shoots in the next growing season.
- — Within a compound there is typically a primary bud, a smaller secondary and tertiary buds.

2) Prompt buds: Form and break open in the same growing season
- - they form on the main shoot (that has just grown from a compound bud) and produce lateral shoots

Question 10

Whats the difference between the primary, secondary and tertiary buds?

Answer 10

1) The primary: the main growing point

2) the secondary and tertiary buds usually only grow if damage has occurred to the primary bud(eg springfrost)

Question 11

What is the essence of lateral shoots ?

Answer 11

1) they grow from prompt buds formed in the current year

2) They have a stem, leaves, buds, tendrils and sometimes inflorescences
3) Their main function is to allow the plant carry on growing if the tip of the main shoot has been damaged or eaten

4) they can provide an additional source of leaves for photosynthesis
- - which can be useful if the laterals are near the end of the main shoots and able to benefit from sunlight

5) Growth of laterals nearer the base of the main shoot can be undesirable as they impede air flow and can shade the fruit too much, they may be removed in summer pruning

Question 12

Can lateral shoots produce inflorescences ?

Answer 12

Yes and theyre known as a second crop, but it depend on the grape variety and canopy management techniques

eg: pinot noir is an grape variety that often forms inflorescences on lateral shoots.
- - they form bunch of grapes later than on the main shoot and ripen slower than the main

Question 13

What if you harvest the main crop and the second crop at the same time ?

Answer 13

The second crop will be:

• higher in acidity
• lower in potential alcohol
• may have unripe tannins and aroma/ flavours
• in black grapes: less colour development.

—-so its the winemakers choice to remove the second crop during the summer pruning

Question 14

why removing the second crop dure summer pruning ?

Answer 14

This technique is thought to enhance the ripening proces and improve the uniformity of ripeness of the remaining bunches

• • if the fruit is handharvested, than its easier to select the bunches
• – but if machine harvested, the second crop will influence the must and finishing wine

Question 15

whats the function of tendrils ?

Answer 15

The shoot cannot support itself, that’s what the tendrills do

• in the wild the tendrills attach themself on other vines, plants or trees, providing support.
• in the viticulture, grape growers can use a trellis to position the vine canopy
• — the tendrils curls around trellis wires and keep the canopy in place
• — grapegrowers do not alwas trust the tendrils to hold the vine on the trellis, so they tie canes and shoots also on the trellis

Question 16

What is the function of the leaves?

Answer 16

The leaves are the main site of photosynthesis in the vine.

The sugar produced in photosynthesis are used for vine growth and metabolism

1) the stomata (pores) open the underside of the leaves; letting water diffuse out and CO2 for photosynthesis in.
2) these stomata partially close if the vine is waterstredded
3) this can help conserve water, but limits the photosynthesis by preventing CO2 from entering the vine

Question 17

what can you tell me about the proces called transpiration ?

Answer 17

As water diffuses from the leaf, the transpiration process will draw water and nutrients from the soil up through the the vine to the leaves

Question 18

What is photosynthesis ?

Answer 18

photosynthesis produses energy (carbohydrates), in the presence of sunlight , from CO2 and water (with oxygen as byprodcuct, which is respired ( uitgeademd)

Question 19

What is waterstress ?

Answer 19

If there is a watershortage, the vine can temporarily stop transpiration in order to preserve its resources

during a prolonged shortages or drought, vines suffer from water stress: photosynthesis stops, leaves wilt and grapes fail to ripen a.
–ultimately this can weaken and kill a vine

Question 20

What is a inflorescense

Answer 20

it’s a cluster of flowers on a stem, which becomes a bunch of grapes at fruit set.

– the number of inflorescences on each main shoot can depend on the grape variety , but is usually between one and three.

Question 21

What is a bunch ?

Answer 21

A bunch of grapes is a fertilised inflorescence.
- usually not all the flowers inthe inflorescence will succesfully become grapes.

– the characteristics of the individual grapes, as well as the size and shape of the bunch, varies between grape varieties and even between different clones of the same grape variety.

— some grape varieties can have very tight bunches (eg pinot noir) which are more prone to fungal diseases inside the bunch to the grape skins

Question 22

What is coulure ?

Answer 22

Fruit set occurs when a flower starts to develop into a grape. Not every flower becomes a grape and after fruit set unpollinated flowers drop off.

— if more flowers than normal fail to fertilise, this condition is called coulure.

Question 23

what is millerandage ?

Answer 23

Low temperature results in a mix of small, seedless berries, which can ripen normally and larger, seeded berries

Question 24

What weather conditions cause millerandage and coulure ?

Answer 24

Low temperature, cloudy and rainy weather during the pollination period

Question 25

A grape is made of ?

Answer 25

1) Pulp
2) Skin
3) Seeds
4) Bloom
5) Stem

Question 26

What can you tell me about the pulp ?

Answer 26

The pulp makes up the majority of the grapes weight and volume. it contains:

• Water
• Sugars
• Acids
• Some aroma compounds

Water is the largest single component in a grape’s pulp.
Sugar is the second largest component and is of vital importance: the yeast will use it to make alcohol
– acids are also found in the pulp, the most abundant is tartaric acid followed by malic acid.

The pulp of most grapes is colourless. exceptions include teinturier varieties, which have red- coloured pulp (eg alicante Bouschet); however these are not common.

Question 27

What’s the effect of the skin ?

Answer 27

1) A grape’s skin and the area immediately beneath contains a high concentration of flavour compounds, which gives each grape its signature varietal character
2) tannins: a large number of chemical compounds are classed as tannin. at veraison they taste verry bitter and astringent and, as the grapes ripen the level of bitterness and astringency falls
- - the amount of tannins and colour in black grapes is significantly higher than in white grapes

Question 28

What can you tell me about seeds ?

Answer 28

Seeds mature inside te grape. seeds and stems contain tannins.

• if the seed matures it turns yellow to dark brown.
• • seed contain oils, tannin and the embryo, which can grow into a new plant.

Question 29

Whats the bloom ?

Answer 29

Its the waxy surface that covers the skin of the grapes and contains yeast that can be used to ferment the wine.

Question 30

What about one year old wood ?

Answer 30

a) main shoots from the last growing season that were kept at pruning.
b) the amount of one year old wood will depend on the pruning and training decissions made by the grape grower.
c) the one year old woods supports the compound buds that will break to release the main shoots for the upcoming growing season.
d) Depending on how the vine is pruned the one year old wood will either be called a cane or a spur

Question 31

What is the permanent wood ?

Answer 31

a) Woody parts that are older than one year, including the trunk
b) depending on pruning and training decisions, some vines also have one or more horizontal arms of permanent wood, often called Cordons
c) The trunk and cordons provide support for the other parts of the vine
d) They transport water and solutes to and from different parts of the vine and store carbohydrates and nutrients

Question 32

What is the function of the roots ?

Answer 32

1) the roots are important for anchoring the vine and also for the uptake of water and nutrients
2) they’re also a store of carbohydrates and produce hormones that have important functions within vine growth and grape ripening
3) Most of the vine’s roots are found in the top 50 cm of the soil (sometimes 6 meters)
4) Distribution of the main framework of roots is influenced by the soil properties, irrigation, cultivation an the type of rootstock
5) The water and nutrients are absorbed at the root tips, where the roots are actively growing