WSET Advanced Chapter 1 Grape Species, Varieties and Rootstocks AKC1 Flashcards
Vine Species
Vitis Vinifera (for fruit)
Clones
Select specimens of a specific variety are propagated for their favorable characteristics that have emerged through generations of mutations.
Crossings
Any variety that is grown from seed whose parent vines were both Vitis Vinifera
Hybrids
Any variety that is grown from seed whose parents were from different vine species. Used for rootstocks, not fruit.
Rootstocks
Rootstocks are used because the pest Phylloxera is fatal to Vitis Vinifera, so it is grafted on the resistant non-Vitis roots. Now rootstocks are designed to protect against nematodes, resist drought, adjust to soil salinity levels and even limit Vinifera growth.
Shoots
New growth a vine produces each year. Along each shoot are regularly-spaced bumps called nodes, where either a leaf and a flower or a leaf and a tendril will form. Buds form where leaf stems join the shoot.
Leaves
Responsible for photosynthesis, which uses chlorophyll and sunlight to turn water and CO2 into sugar glucose and oxygen.
Tendrils
A twisting, threadlike structure by which a twining plant (vine) grasps an object for support. They wrap around trellis wires to support the vine.
Flowers
Flowers are the vines reproductive organs, and are hermaphroditic. They group into infloresences, and as each pollinated flower will become a berry, each infloresence will become a bunch of grapes.
Buds
Form in the joint between the lead and the shoot, and are embryonic shoots, growing for next year.
One Year Old Wood
Shoots turn woody during the winter after their spring sprout. This wood is pruned into a “cane” (8-15 buds) or a spur (2-3 buds)
Permanent Wood
Wood older than 1 Year. It is the arms and trunk of the vine, sometimes call Cordons.
Roots
Absorb water and nutrients from the soil, anchor the vine and store carbohydrates so wine can survive the winter.
Origin and Number of Wine Varieties
Between 5000 and 10000 type of Vinis Vinifera.
Varietal, Cultivar and Variety
All words for a grape variety.
Cutting
A section taken from a healthy shoot before it becomes woody. It is planted, takes root, and becomes a new plant.
Layering
A method of propagation where the root is bent down into the ground. The buried section takes root, and then the cane is cut.
Clonal Selection
A method of propagation that began in the 1950s, where a single plant with the most favorable characteristics is selected. This reduces genetic variation, which can increase disease risk and insures uniform wine, for better or worse. Also, characteristics which were desirable in the 1950s (high yield) may come at the expense of quality.
Phylloxera
A louse brought to Europe in mid-19th Century, weakened the unresistant Vitis Vinifera’s roots, exposing it to bacteria and fungi. American vines clog the pest’s mouth with sticky sap and form protective layers behind wounds to prevent serious infection. There are serious quarantine procedures in Chile, Argentina and South Australia.
Grafting
The technique used to join a hybrid rootstock to a Vitis Vinifera variety.
Bench-Grafting
A method of grafting a Vitis Vinifera to a rootstock. Two short canes of equal width are cut from a rootstock and a Vitis Vinifera, spliced together with a machine and allowed to heal in a warm, humid environment until the wounds heal into a callus. Then, roots are trimmed off the Vinifera, the shoots off the rootstock, and it’s planted or stored for a year.
Head-Grafting
A method of grafting a Vitis Vinifera to a rootstock that is used when a Grower wants to change varietals in a single year, instead of three, and it is cheaper than replanting the whole vineyard. The existing vine is cut back, and a the new variety is grafted onto the trunk.
