The Vine Flashcards
Major Vine Species
Eurasia: Vitis vinifera
North America: Vitis labrusca, Vitis riparia, Vitis rupestris, Vitis berlandieri
Anatomy of a vine
Shoots
One year old wood
Permanent wood
Roots
Structure of shoots
Shoots grow from buds retained from the prior year
Major components: buds, leaves, tendrils, lateral shoots, inflorescences (grape bunches)
Swellings along the shoots where other things are attached are nodes; length b/n are internodes
When the green shoots become woody and lignify they become canes
Buds
Form between the leaf stalk (petiole) and the stem
Mature to contain all the structures in miniature that will become green parts of the vine: stem, buds, tendrils, leaves, and often inflorescences
Two types:
Compound (latent) form in one growing season and break open in next. Produce shoots in next season. Within there is usually a primary bud (main growing point) and smaller secondary and tertiary which only grow if first is damaged.
Prompt buds: form and break open in same season. form on primary shoot and produce lateral shoots.
Lateral Shoots
Grow from buds formed in the current year (prompt).
Smaller and thinner than primary; have stem, leaves, buds, tendrils, sometimes inflorescences
Allow plant to continue growing if primary is damaged. Can provide more leaves for photosynthesis. So better near the end of a primary nearer to sunlight vs at the base where they may impede air and shade fruit.
Often produce inflorescences (second crop). Pinot often does. These become bunches later and ripen later. May be removed by green harvesting. Or during hand harvesting. If not can impact flavor.
Tendrils
In the wild latch on to things like trees for support. In a trellised vineyard the trellis provides support so the tendrils may latch but don’t do anything.
Leaves
Main site of photosynthesis. Sugars produces are used for vine growth and metabolism.
Stomata (pores on underside of leaf) open to let water diffuse out and CO2 in.
Water leaving is transpiration and draws water and nutrients up from the soil.
Stomata partially close if vine is water stressed. This can conserve water but limits photosynthesis by preventing CO2 from entering.
Inflorescences
Cluster of flowers on a stem, which becomes a bunch of grapes at fruit set. Usually between one and three per shoot.
Bunches
A bunch of grapes is a fertilized inflorescence
Usually, not all flowers become grapes
Grapes
Type of berry made of pulp, skin, seeds
Pulp: majority of a grape’s weight and volume. Contains water, sugar, acids, and some aroma compounds and precursors. Usually colorless except for teinturier varieties (alicante bouschet).
Skin: Contains high concentrations of aroma precursors, tannins, and color compounds. Tannin and color compounds sig higher in black grapes.
Seeds: Mature inside grape turning yellow to dark brown. Contain oils, tannins, and embryo which could be a new plant.
Bloom: powdery, waxy coating coving the surface of the grape.
Stem: attaches grape to the vine and contains tannins.
One year old wood
Shoots from previous growing season that were not removed at pruning.
Amount depends on pruning and training decisions.
Supports compound buds that will break to release shoots for upcoming growing season.
Can be either a can or a spur depending on pruning.
Permanent wood
Woody parts of the vine older than one year, including trunk.
May also have one or more horizontal arms of permanent wood called cordons.
Trunk and cordons support the other parts of the vine, store carbohydrates and nutrients, and transport water and solutes.
Roots
Anchor the vine and take up water and nutrients.
Store carbohydrates and produce hormones that have an important function for growth and ripening.
Typically, vines are grafted onto rootstock.
Most roots are in top 50cm of soil, though have been found to reach over 6 meters down.
Root distribution is influenced by soil properties, irrigation, cultivation, and rootstock.
Vine propogation
Cutting: section of shoot that is planted and grows into a new plant. Most common as many cuttings can be taken and propagated at the same time. These can be grafted onto rootstocks. Can be treated for disease.
Layering: Using shoots from a neighboring established plant. Cane bent down with a section underground and tip above. Buried part takes root and once established, cut off from original. Grows on own roots not rootstock.
These two are genetically identical to the parent.
Vines that grow through seeds are not
Clones
Occur when a random mutation occurs in the genetic code. May result in no effect or noticeable (smaller berries, tighter bunches, etc.).
Those with favorable are selected and propagated via cuttings. This is called clonal selection.
Pinot Noir has several: Clone 115 has low yields of small grapes, 521 higher yield of larger grapes for sparkling
Sometimes so significant produces a new type Pinot Noir, Meunier, Gris, Blanc as ex.
Having all the same clone in a field can ensure even ripening but less diversity could mean less complexity or more disease susceptibility.
