4 - The Vine Flashcards
What are the most important vine species in modern viticulture?
Vitis vinifera - main Eurasian species. Produces nearly all grapes used for wine.
American vines - there are 3 important species native to North America. These are resistant to Phylloxera unlike vitis vinifera so are used for rootstocks that vitis vinifera is grafted onto. wines they produce themselves unattractive flavors
what are factors other than color and flavor a grape grower will consider when selecting grape?
budding and ripening times
resistance to disease
What is a section of a vine shoot that is planted and then grows as a new plant?
Cutting
What is layering?
A cane is bent down and buried in the ground. The buried section takes root and the cane linking the original plant to the new growth is cut.
Why do most grape growers use cuttings instead of layering?
Due to risk of phyloxxera
Why and how are new clones formed
vines with positive mutations (i.e. better quality fruit or disease resistance) are selected for further propagation by cutting or layering.
Rather than waiting for random mutation, new varieties can be created. How does this happen?
cross-fertilisation (pollen from male port of flower of one vine, is transferred to female part of flower of another vine). The pollinated flower develops into grape with seeds. When seeds are planted, it grows into new variety because of different genetic material from its parents. (even if parent vines are from the same grape variety).
What are the 4 parts of a vine?
- the green part of the vine: parts of vine that grow each new year. mostly the shoot, along with leaves, buds, tendrils and flowers/berries. the buds are the miniature of what will be shoots, leaves, flowers and tendrils next year.
tendril supports vine by winding itself around supporting structure like trellis. flowers are the reproductive organs of vine. vine’s flowers have male and female parts and are grouped in inflorescences - each pollinated flower becomes berry. - one-year-old wood: shoots turn woody the winter after they have grown. the next spring they became one-year-old wood, and buds on them turn into shoots.
- permanent wood: wood that 1+ year old. pruning restricts amount of permanent wood.
- the roots: function of roots is absorb water and nutrients from soil, anchor vine, and store carbohydrates that noursih vine during winter.
When a new variety is produced from two parents of the same species, what is it called?
crossing. this term is usually reserved for new varieties bred by researchers. for instance muller thurgau is a crossing of Riesling and Madelein Royale (both varieties of the vitis vinifera species)
what is a vine whose parents come from different vine species?
hybrid. typically they have one American vine as a parent. these are important as rootstocks
What is phylloxera?
an insect, native to North America that caused destruction Europe’s vineyards when it was introduced accidentally 19th century. American vines are able to inhibit it by clogging its mouth with sticky sap.
besides offering protection against phylloxera what other benefits do rootstocks have?
rootstocks can be used to protect against nematodes, provide resistant to drought
what are the two main forms of grafting?
bench grafting: most popular. automated process. short sections of cane from v.vinifera and rootstock are joined by machine. the two parts fuse together and can then be planted.
head grafting: used to switch an established vineyard over to a different grape variety. Existing vine cut back to its trunk. new variety is grafted onto the trunk. unlike newly planted vine, this technique produces fruit at next vintage.
