The Vine Flashcards
Two important species in modern Viticulture (grape growing)
A - Vitis Vinifera (main Eurasian species)
B - American vines (rootstocks)
Vitis Vinifera has how many grape varieties
Thousands
Principle differences for consumers between grape varieties
Colour
Flavour
(both come from the grape itself)
Grape selection criteria / factors
- budding times
- ripening times
- colour
- flavour
- disease resistance
Can grapes be grown using seeds
No
To preserve unique grape varietal (cultivar) qualities
- cutting
- layering
(new plant is identical to original)
Cutting is
a section of a vine shoot (green) that is planted and then grows as a new plant (widely used in commercial nurseries)
Layering
Used in the vineyard, bend down a cane, bury a section, make sure the end / cane tip is pointing upwards out of the ground. When the section takes root, the part connected to the original plant is cut. Not used as much now because of phylloxera risk.
Grape variety is a
group of individual plants that can trace their lineage back through series of cuttings and/or layerings to a single plant
Vine variety = grape variety
Variety = cultivar
Individual grape varieties are genetically identical, but
Mutations sometimes occur when the vine grows
Positive mutations result in
better quality fruit
better disease resistance
Vines with positives mutations are
selected for further propagation by cutting or layering
Clonal section is
vines with positive mutations that are selected for further propagation by cutting or layering
In grape growing, each individual vine or group of vines that shows a particular set of unique characteristics is known as a
clone
Clone differences are often small and clones are still considered
to be from the same grape variety
When ordering new plants, growers often
specify which clone they would like in addition to the grape variety
Significant effect mutations mean
resulting plants are treated as a new variety (even though they are still clones of the original plant)
Ancient variety Pinot resulted in
grape varieties Pinot Blanc, Pinot Gris, Pinot Noir, and Meunier
Researchers searching for grape varietals to thrive in
certain climates
soil conditions
improved disease resistance
Cross fertilisation Creates a New Variety by
Pollen from a male part of the flower of one vine is transferred to the female part of the flower on another vine and fertilisation occurs, then the new grape & seeds are planted creating a new variety
Genetic material of cross fertilisation is different
from the two parent plants - even if the parent vines are from the same grape variety
New varieties come to market
infrequently, because consumers resist new varieties
With seed planting, growers
must wait at least 2-3 years before vines flower and produce grapes to see the new characteristics
Grapevine genetics are now used
by scientists to select offspring with characteristics they desire
Crossing
New variety produced from two parents of the same species
Cabernet Sauvignon
Cabernet Franc X Sauvignon Blanc
Bred by researchers, Muller Thurgau is
Riesling X Madeleine Royale
Bred by researchers, Pinotage is
Pinot Noir X Cinsault
Hybrids are
vine whose parents come from at least two different vine species (typically have one American vine as a parent)
American vines are
Rarely used for winemaking, but crucial role for rootstock
Vidal (grown in Canada for icewine) is
a hybrid used for wine
Phylloxera is
an insect (underground louse) that lives underground and feeds on a vine’s roots
American vines are resistant
to Phylloxera by clogging its mouth with sticky sap, and form protective layers behind the feeding wound preventing secondary infections
Where is Phylloxera NOT a problem
Chile, some parts of Argentina and South Australia
What protects against Phylloxera
Only strict quarantine procedures - it cannot be controlled with chemicals
What struck Europe in the late 19th century
Phylloxera - Vitis Vinifera was not resistant, but American Rootstock could be used by graft
Rootstocks can also
protect agains nemadtodes
provide better drought resistance
Grafting is the technique
used to joint a rootstock to a Vitis Vinifera variety
What are two main types of grafting?
Bench grafting, and
Head grafting
Bench grafting happens
by a specialist in a plant nursery - short cane sections of both varieties are joined by a machine and stored in a warm environment encouraging the two parts to fuse
Head grafting happens
in the vineyard when an established vineyard decides to switch varieties between seasons
What is head grafting?
Existing vine is cut back to its trunk, a bud or cutting of the new variety is grafted to that trunk.
Why head graft?
- If head graft is successful, the new variety will produce fruit that next year,
- cheaper than replanting a whole vineyard
- variety starts life with an established root system
- allows grower to quickly adjust to market demand
Newly planted vines take how long to produce a commercially viable crop
at least three years
Vidal, a French hybrid is from
Ugni Blanc (trebbiano) plus Seibel 4986 (Rayon d’or)
Makes good icewine in Canada
Vines have four sections
- green parts
- one year old wood
- permanent wood (trunk)
- roots
Green parts, grow new each year and include
- shoot (principal structure)
- leaves
- buds (between leaf and shoot become next years shoots)
- tendrils (supporting structure)
- flowers or berries
One year old wood is a
shoot that turned woody during the winter after it grows green
One year old wood management is vital because
vines will normally only produce fruit on shoots that grow from buds that developed the previous year
Every winter the vine is pruned to either a
Cane or
Spur
A cane is one year old wood with
length
8-20 buds
A spur is one year old wood with
short piece of one year old with two to three buds
Permanent wood is
more than one year old, and made up of truck and (where present) arms of the vine
The amount of permanent wood is
restricted by pruning
Roots function to
- absorb water and nutrients from the soil
- anchor the vine
- store carbohydrates to allow the vine to survive winter
In modern vineyards, most vitis vinifera are
grafted onto other species’ root systems that are phylloxera resistant
Vine Arm is also called
Cordon and is permanent wood
One year old wood can be either a
Cane (8-20 buds) or a
Spur (2-3 buds)
Head grafting is often
- canes held into place with tape
- painted with pruning paint to protect the wound
Newly planted bench grafted vines are often
protected with wax at the joining location between the two sections of cane
