The Vine and Growing Environment Flashcards
benefits of grafting
- american rootstock protects against phylloxera
- rootstocks are resistant to nematodes, drought and alkaline soils
what is head grafting and why is it used
head grafting = vine’s head cut off the trunk and the cutting of a new variety is grafted on the trunk
why = switch out varieties instead of uprooting and replanting and anti-phylloxera
produces the fruit after 1 year
what is cross-fertilization and why is it useful
when one takes the pollen from the male part of the flower of a vine and fertilizes the female flower of a different vine and create a new grape variety.
why =
1. create a disease resistant variety
2. adopt new grape to climate extremes/drought
3. increase quality/yields
explain grafting and its goal
procedure used to fuse bud wood of a desired variety onto another rootstock. goal = phylloxera resistant vine
2 different ways of propagating a vine
- layering
- cutting
what is layering
when the vine’s 1yo cane is bent into the ground and partially buried with the tip of the cane poking out. buried part grows roots.
–> done in the vineyard
what is cutting
when a section of a shoot is cut off from an existing vine and planted to grow a brand new plant
–> done in the nursery
what is clonal selection
when a vine naturally mutates and its new positive characteristics are propagated by cutting/layering
places in the world that are free of phylloxera
Chile, South Australia, Argentina
crossing of Cab Sauvignon
Cabernet Franc X Sauvignon Blanc
Crossing of Muller Thurgau
Riesling x Madeleine Royale
Crossing of Pinotage
Pinot Noir x Cinsault
difference between crossings and hybrids
crossings: new varieties by crossing parents of the same species
hybrids: at least 2 different vine species
4 main parts of a vine
- roots
- permanent wood
- 1 yo wood
- green parts
what is the importance of a vine’s leaves
via photosynthesis they use sunshine to convert water and CO2 in glucose and oxygen
what is earthing up
when there are very low temperatures, it is important to cover the graft of the vine
what are continentality and diurnal range
variation between summer and winter in temperature and day-night time
what do cool nights provide to the grapes
slow loss of aromas
high acidity during ripening
what do warm nights provide to the grapes
accelerate ripening
characteristics of the mediterranean climate and where
- low temp difference between hot&cold months
- summer warm & dry
- in South Rhône, South France, Greece, Italy and Spain
characteristics of the maritime climate and where
- cool moderate temp
- low annual difference between hot and cold months
- rainfall evenly spread
- Bordeaux, Nantais, Portugal and NZ
characteristics of the continental climate and where
- big difference in temp between hot and cold months
- short summers with large temp drop in autumn
- Burgundy, Alsace, Northern Rhône, Germany, Austria, Canada
what are the 5 elements that a vine needs
- heat
- sunlight
- CO2
- water
- nutrients
what is powdery mildew
- in hot/shady/humid environments
- grey/white powdery coating
- solution: sulfur based spray
what is downy mildew
- in warm/wet/humid environments
- yellow spots on the upper side of the leaf and furry grey patches on the underside.
- solution: copper based spray (=bordeaux mixture)
what are the 2 main types of vine training
- head training
- cordon training
describe cordon training and how is it pruned
trunk with usually 1-2 permanent arms/cordons
- usually spur-pruned
- easier to harvest mechanically
define pruning and when are vines pruned
remove unwanted leaves and permanent wood
- winter and summer
purposes of summer pruning
- control canopy
- force sugar production in the grape
- give the grapes favourable sun exposure via leaf stripping
what is spur pruning
short sections of 1yo wood that have been cut down to only 2-3 buds.
- distributed along the permanent wood or around the top of the trunk
what is replacement cane pruning
only 1-2 canes are retained and each cane is tied horizontally to the trellis for support
- guyot training
describe head training and how is it pruned
usually just a trunk (not a lot of permanent wood)
- spur pruned or replacement cane pruned
- bush vines –> head trained, spur pruned
- guyot vines –> head trained –> cane pruned
what are the functions of a vine’s roots
- absorb water + nutrients
- anchor the vine
- store carbs over winter to keep plant alive
what are the reproductive organs of a vine
flowers
what is inflorescence
cluster of flowers
purposes of winter pruning
- choose the number + location of buds that will form shoots in the growing season
- ensure buds are not too close to eachother
3 reasons to use a trellising system instead of bush vines
- control amount of sunlight
- improve air circulation
- improve mechanical harvesting and distribution of sprays
2 examples of head trained vines
- guyot
- bush
synonim of a bush vine
“Gobelet” –> untrellised
what is the most widely used trellising system
VSP –> vertical shoot positioning
describe VSP and why
shoots are positioned in an upwards direction attached to trellis wires –> narrow canopy
- allows good air circulation and grapes are exposed to direct sunlight
what pruning can VSP be used with
- cane
- spur
for viticulture it is more desirable a fertile or barely fertile soil
barely fertile –> stressed vines make good wine
what does yield measure
quantity of grapes produced in weight or volume
what is veraison
onset of ripening and when grapes change colour
what happens to grapes during berry ripening
- sugar increases
- acid decreases
- tannins develop and become less astringent
what are nematodes and what damage do they cause
worms that attack a vine’s roots –> leave open wounds that interfere with water and nutrient uptake
what are the treatments or cures for bacterial diseases
NONE –> only solution is uprooting and sanitize land
top three most important nutrients for vines
- nitrogen
- phosphorus
- potassium
what is chlorosis
nutrient deficiency in the soil that affects the vine’s ability to photosynthesize
when does budburst happen in each hemisphere
- north hemisphere: march- april
- southern hemisphere: sept-october
during what months does flowering occur in north/south hemisphere
north: may/june
south: november/december
what is the optimal weather during flowering
warm temp, plenty of sunshine and little/no rain
frost is most dangerous in which phase of the vine’s annual cycle
during budburst.
what is couloure
when a flower doesn’t turn into a berry
what is millerandage
poor or irregular fruit set due to cold, rainy conditions during pollination
what effect can drought have on a vine
water stress
3 most important irrigation systems
- drip irrigation
- sprinklers
- flood irrigation
which soil has the highest water retention
clay
how many years after planting a new vineyard wines will produce a usable crop
3rd year after planting
list a vine’s annual cycle
- budburst
- first shoot/leaf growth
- flowering
- fruit set
- véraison
- ripening
- harvest
- dormancy
what is the effect of the gulf stream in europe
adds a warming effect to the climates of north and west europe
what is the cold ocean current that affects south africa
Benguela current
name the cold ocean current that affects chile
humboldt current
two things that can reduce diurnal range
- proximity to body of water
- cloud cover
how does cloud cover affect a vineyard
- slow flowering and fruit set
- stop grapes from fully ripen
what temp can vines be damaged/killed by a deep winter freeze
-20°C
4 protections against frost
- heaters
- fans
- sprinklers
- vineyard design
growing season months in north/south hem
north: april-october
south: october-april
cool climate temperature
16.5°C and below
moderate climate temperatue
16.5°C-18.5°C
warm climate temperature
18.5°C-21°C
hot climate temperature
21°C+
what do vines use to fuel growth and ripen grapes
- glucose
- nutrients from the soil
