1 The Vine Flashcards
There are over —— known grape varieties in the world, but the vast majority of these varieties belong to one species, Vitis vinifera.
a thousand
There are over a thousand known grape varieties in the world, but the vast majority of these varieties belong to one species, ———.
Vitis vinifera
Vitis vinifera is indigenous to —-
Eurasia.
American vine species are also used in wine production in some regions (e.g. New York State), but their main function globally is as —— .
rootstocks on to which V. vinifera
is grafted.
The most important North American species are
Vitis labrusca,
Vitis riparia,
Vitis berlandieri and
Vitis rupestris
All vines have a similar structure. This structure can be divided into four sections, which are:
the shoots,
one-year-old wood,
permanent wood,
and the roots
What is canopy?
The shoots and all of their major
structures – buds, leaves, lateral shoots, tendrils and inflorescences/grape bunches – are
collectively called the canopy.
The shoots on the vine grow in —– from buds retained from the previous year.
spring
The shoots on the vine grow in spring from ———.
buds retained from the previous year
The major structures of the shoots are:
the buds,
leaves,
tendrils,
lateral shoots
inflorescences or
grape bunches
What are solutes?
Solutes are substances like sugars and minerals that dissolve
in a liquid to form a solution
What are the main jobs of the main axis of the shoot?
transports water and solutes to and from the different structures and it is a store of carbohydrates
The little swellings along the shoot,
where the other structures are
attached, are called —–.
nodes
The lengths in between the nodes
are called ——-.
internodes
What does it mean when we say the green axis lignify?
In late summer, the leaves fall from the vine and the green shoots lignify (become woody, rigid and brown) from this point they are called canes.
In —— the vine will be
pruned to leave the necessary
structures for the next growing
season
the winter
What is petiole?
the leaf stalk
Where do the buds form?
Buds form between the leaf stalk (petiole) and the stem
What does a bud contain?
they contain all the structures in miniature that will become green parts of the vine, including the stem, buds,
tendrils, leaves and often inflorescences.
What are the two main types of buds?
Compound buds
Prompt buds
What is another name for Compound buds?
latent buds
These buds form in one growing season and break open in the next growing season (provided they are retained during winter pruning). They produce the shoots in the next growing season.
Compound buds
Within a compound bud, there is typically a primary bud (the main growing point) and smaller secondary and tertiary buds. Fact or fiction?
Fact! The secondary and tertiary buds usually only grow if damage has occurred to the primary bud (e.g. spring frost).
These form and break open in the same growing season. They form on the primary shoot (that has just grown from a compound bud) and produce lateral shoots.
Prompt Shoots
These shoots grow from buds formed in the current year (prompt buds)
Lateral
Lateral shoots are smaller and thinner than the primary shoots.
True
What is the main function of lateral shoots?
Their main function is to allow the plant to carry on growing if the tip of the primary shoot has been damaged or eaten.
The process by which green plants use sunlight to produce sugars from carbon dioxide and water.
photosynthesis
How can lateral shoots contribute to the process of photosynthesis, and under what conditions are they most effective in providing additional leaves for this process?
Lateral shoots can provide an additional
source of leaves for photosynthesis which can be useful if the laterals are near
the ends of the primary shoots and able to benefit from sunlight.
What is summer pruning for?
Growth of laterals nearer the base of the primary shoot can be undesirable as they impede air flow and can shade the fruit too much. They may be removed in summer pruning.
What shoots often produce inflorescence?
Lateral shoots often produce inflorescences, which can be known as a ‘second crop’.
What is second crop?
Lateral shoots that often produce inflorescences
Name one grape variety that often forms inflorescences on lateral shoots
Pinot Noir
When do the inflorescences on lateral shoots become grapes?
These inflorescences become bunches of grapes later than those on the main stem and hence ripen later.
What will be the characteristics of grape bunches on lateral shoots if harvested at the same time as the main crop?
will be higher in acidity,
lower in sugar and
may have unripe tannins and aromas/flavours and,
in black grapes, less colour development
The shoot cannot support itself, therefore vines have——
tendrils
In the wild, tendrils would
have enabled the vine to attach itself to other plants or trees. In viticulture, grape growers use a —— to position the vine canopy
trellis
Grape growers typically do not trust the tendrils to hold the vine to the trellis on their own and therefore they ——- .
tie in canes and shoots
The —- are the main site of photosynthesis in the vine
leaves
The —— produced in photosynthesis are used for vine growth and metabolism.
sugars
——- open on the underside of the leaves, letting water diffuse out and carbon dioxide for photosynthesis to enter.
Stomata (pores)
A process called ——- draws water and nutrients
from the soil up through the vine to the leaves.
transpiration
Stomata ——- if the vine is water stressed.
partially close
What is the effect of partially closed stomata?
This can help conserve water, but limits photosynthesis by preventing carbon dioxide from entering the vine.
The ——- is a cluster of flowers on a stem, which becomes a bunch of grapes at fruit
set.
inflorescence
The number of inflorescences on each shoot
can depend on the grape variety but is usually between ——-.
one and three
