Ch 4 The Vine

Question 1

What are the main species of vine?

Answer 1

Vitis Vinifera ( Eurasian)
American vines e.g.
* v. Labrusco
* v. Riparia
* v. Rupestris
* v. Berlandieri

Question 2

Why is v. Vinifera preferred for winemaking?

Answer 2

It has evolved over thousands of years and produces attractive aromas and flavours. American vines are thought to have unattractive flavours.

Question 3

What is the main use for American vines?

Answer 3

Because its rootstock is tolerant of diseases such as phylloxera and nematodes and will tolerate tougher climates, eg drought, it is used to graft on v. Vinifera to get the flavour and protection.

Question 4

What is a grape/vine variety?

Answer 4

A group of individual plants which can trace it’s lineage back through a series of CUTTING or LAYERING to a SINGLE PLANT. Note they are GENETICALLY IDENTICAL VINES

Question 5

What is a cutting?

Answer 5

A section of dormant vine shoot is taken and regrown to a new plant. (Commercial nursery method)

Question 6

What is layering?

Answer 6

A cane from an existing vine is bent down into the ground and part of it is buried until a new root establishes and a vine begins to grow. It is then cut off from “mother vine”. Note it is not resistant to phylloxera.

Question 7

What is a “ CLONE”?

Answer 7

As a result of mutation during growing some vines develop positive characteristics, eg disease resistance, higher quality/volume fruit. Any individual or group of vines which display these unique characteristics is known as a CLONE.

Question 8

What is CLONAL SELECTION?

Answer 8

Vines that show positive characteristics are propagated to create future vines that have these characteristics.

Question 9

Why might a new variety be sought?

Answer 9

To thrive in certain climates/ soil;
To improve disease resistance;
To produce a higher quantity/quality of fruit

Question 10

What method is used to try to create a new variety?

Answer 10

Cross-fertilisation - pollen is transferred from the male part of a flower of one variety to the female part of a different variety. Develops into a grape with seeds which are planted. If they grow it is a new variety.

Question 11

What is a crossing?

Answer 11

A new variety created from 2 parents of SAME species is a Crossing. Most commonly used to describe varieties grown by researchers e.g. PINOTAGE, MULLER-THURGAU. There are wild crossings eg Cab Franc + Sauv Blanc = Cab Sauv

Question 12

What is a hybrid?

Answer 12

A hybrid is a variety grown from 2 different SPECIES i.e. at least one American species.
(Uncommon but note VIDAL in Canada)

Question 13

Name 4 parts of the vine.

Answer 13

Green parts;
One year wood;
Permanent wood;
Roots

Question 14

Name the 5 green parts of the vine.

Answer 14

Shoot, tendrils, leaves, buds, flowers+ berries

Question 15

What does the shoot provide?

Answer 15

The shoot provides structure, ie the stem

Question 16

What is role of leaves?

Answer 16

Leaves are the lungs/engine of the plant. They facilitate photosynthesis which converts water and CO2 into glucose and O2. The glucose ripens the grapes.

Question 17

What are the buds?

Answer 17

The buds are embryonic shoots which develop during a year and contain the necessary components for a shoot the following year.

Question 18

What do the tendrils do?

Answer 18

They cling to any structure(eg trellis) as the vine cannot support itself.

Question 19

What do flowers and berries do? What is another namefor these?

Answer 19

The flowers are the reproductive organs of the plant. They have male and female parts which when pollinated produce berries which will eventually become grapes. Also known as INFLORESCENCES

Question 20

What is one-year wood?

Answer 20

Shoots will turn brown in the winter. The following spring they become 1 year old wood. and need to be pruned back either as “canes” or “spurs”. Fruit will only be produced from shoots which were buds in the previous year.

Question 21

What is “permanent wood”?

Answer 21

Permanent wood is more than 1 year old eg trunk and arms (cordon) and is pruned each year.

Question 22

What is the role of the vine’s roots?

Answer 22

To anchor the vine;
To absorb nutrients and water from the soil;
To provide food ( carbohydrates) to the vine during winter.

Question 23

What is phylloxera?

Answer 23

It is a pest from America which was imported by acicdent and destroyed European vineyards in late 19th century. It feeds on vine roots and leaves wounds which get infected and eventually vine weakens and dies.

Question 24

How is phylloxera combatted?

Answer 24

There is no chemical solution. American rootstock are resistant to the pest and therefore V Vinifera is grafted onto it. This gives protection of roots and flavour of V. Vinifera. Quarantine is only other effective method.

Question 25

Name two types of grafting.

Answer 25

Head grafting and bench grafting

Question 26

Describe bench grafting.

Answer 26

Part of an american rootstock cane is grafted to a V.Vinifera cane using a special joint and automated process and stored in a warm environment to fuse together. Commercial use to provide new plants to vineyards

Question 27

Describe head grafting.

Answer 27

Head grafting is used in the vineyard. The existing vine cut back to the trunk and a new bud of the new variety is grafted on. If succesful new variety will grow in next vintage. Used to change variety in established vineyard as it takes bench method three years to produce a crop. Remember Zinfandel and Merlot in California.