High Level D1 Flashcards
Main structural sections of a grape vine
Shoots
One-year old wood
Permanent wood
Roots
Major structures of grape vine shoots
Buds
Leaves
Lateral shoots
Tendrils
Inflorescences/grape bunches
What are the methods for vine propagation
Cutting
Layering
Clonal Selection
Mass Selection
Methods for creating new grape varieties
Seeds
Hybrids
Crossings
Growth Cycles
Dormancy
Budburst
Shoot and Leaf Growth
Flowering and Fruitset
Grape development
Early grape ripening
Veraison
Ripening
Extra ripening
Growing environment influences
temperature
sunlight
latitude
altitude
proximity to water
aspect/slopes
mist, fog, clouds
wind
soil
Describe maritime climate
Low annual difference between coldest and warmest temps
Rainfall spread throughout the year
Describe mediterranean climate
Low annual difference between coldest and warmest temps
Rainfall falls in the winter
Describe continental climate
High annual difference between coldest and warmest temps
Short summers, cold winters
Temps change quickly in spring and autumn
Give temp ranges for cool, moderate, warm and hot climates
Cool - < 16.5 C
Moderate - 16.5 - 18.5 C
Warm - 18.5 - 21 C
Hot - > 21 C
Name main nutrients that grape vines require
Nitrogen
Potassium
Phosphorus
Magnesium
Calcium
Considerations when establishing a vineyard
Site selection
terroir
soil preparations
Planting materials
Grape varieties
Clones
Rootstocks
Considerations when selecting a vineyard site
Price of land
Location, layout, topography
Steep slopes
Will irrigation be required
Ease of access to vineyard
Proximity of vineyard to market, consumers, suppliers
Considerations when preparing the soil in a new vineyard site
Drainage
Structure
Mineral composition
Pests
Unwanted plants
Landscaping
Factors when considering which grape variety to select for a new vineyard site
Style of wine
Yield
Cost
Law
Availability
Market demand
Factors when selecting a grape variety for a new vineyard site
Late/early ripening
Late/early budding
Winter hardiness
Drought resistance
Disease resistance
Vigour
Methods of weed control
Cultivation
Herbicides
Animal Grazing
Mulching
Cover crops
What is cultivation
A method of weed control
Plough soil to cut or disturb the weeds’ root systems
No chemicals - can be used in organic and biodynamic viticulture
Can plough in fertilizers, mow cover crops into soil at same time
Criteria to consider when selecting a rootstock for a new vineyard site
Pests
Vigour
Water
Soil pH
Two types of fertilizers. Give brief description of both.
Organic - derived from fresh or composted plant or animal material - manure, slurry - need to be broken down into inorganic nutrients by organisms
Inorganic - synthetic fertilizers - manufactured from minerals extracted from the ground or synthetic chemicals - provide single or several nutrients - are in inorganic form and readily available to vines
Three types of herbicides
Pre-emergence - sprayed on soil and prevents weeds from growing
Contact - sprayed on weeds and kill green parts of weed that they contract
Systemic - sprayed on weeds and taken in by leaves. Travel up and down weed in the sap and kills the whole plant
What are the key factors of water management
Irrigation
Drainage
What factors need to be considered for irrigation
Sources of water and efficiency of use
Water quality
Amount and timing of irrigation
Types of irrigation
Drip irrigation - most common - cannot be used for frost protection
Flood irrigation
Channel irrigation
Sprinklers - can be used for frost protection
Describe what Regulated Deficit Irrigation (RDI) is
System of timing and regulating the amount of irrigation so vine is put under mild to moderate water stress for specified time during growing season
Scheduled between fruit set and veraison - limit further shoot growth and encourage grape development
What drainage options are available to grape growers
Artificial drainage systems - installed at vineyard establishment
Cover crops - encourage water competition
Improve soil structure - ploughing to improve water flow
Give definition for canopy management
Organization of shoots, leaves and fruit of vine in order to maximize grape yield and quality
Aims of canopy management
Maximize effectiveness of light interception by vine canopy
Reduce shade within canopy
Ensure microclimate for grapes is uniform as possible so grapes ripen evenly
Promote balance between vegetative and reproductive functions of vine
Arrange vine canopy to ease mechanization and/or manual labour
Promote air circulation through canopy to reduce incidence of disease
How does sunlight influence influence grapes (increase/decrease)
Increased sugar levels through greater photosynthesis
Increased tannins and greater polymerization - leads to less bitterness
Enhanced anthocyanin (colour) development in black grapes
Decreased malic acid
Increased levels of favourable aroma precursors and compounds
Decreased methoxypyrazines - herbaceous character (Cab Sauv)
Two cycles related to Vine Balance
Vegetative cycle - Under cropping - Denser canopies -> increased shade -> less fruit growth -> increased shoot growth -> denser canopies
Balanced cycle - over-cropping
Canopy management techniques
Vine training
Winter pruning
Vine trellising
Overall plant vigour mgmt - nitrogen fertilization, irrigation, cover cropping
Summer pruning
Summer pruning techniques
Disbudding - removal of surplus bids
Shoot removal - remove lateral shoots to improve canopy
Shoot positioning - training shoots to trellis as they grow
Pinching - Remove shoot tips to improve flowering
Shoot trimming - limits growth, improves canopy
Leaf removal - reduces shading, disease risk
Crop thinning/green harvesting - remove excess bunches around veraison - encourages ripening of remaining bunches
What is vine density
Number of vines planted per hectare of vineyard
Ranges from a few hundred vines/ha to over 10,000 vines/ha
What does vine density influence in the vineyard
Within-row spacing
Between-row spacing
Consider during vineyard establishment
What considerations are made related to row orientation
North-south orientation best for ripening - most sunlight exposure
East-west - east warmer in the morning, west intense afternoon sun
90 degree angle to prevailing winds
10% slope - planted up and down the slope - machinery may slip
What does the selected training and trellising method depend on?
Vigour of the vine
Topography of the site
Need for mechanization
What is vine training and 2 categories
Shape of permanent wood
Head training
cordon training
Describe head training
Vines have little permanent wood
Consists of the trunk and a few short stubs growing from top of trunk
Can be spur-pruned or replacement cane-pruned
Describe cordon training
Vines have trunk with 1 or more permanent horizontal arms of permanent wood - called cordons
Usually spur-pruned
Takes longer to establish - amount of permanent wood needed
Describe vine pruning and 2 kinds of vine pruning
Removal of unwanted parts of the vine - in winter and summer
Winter pruning - determines number and location of buds that will form shoots in coming growing season - impacts yield
Spur pruning
Replacement-cane pruning
Describe spur pruning
Spurs are short sections of one-year old wood (shoots from last growing season that have lignified) - cut back to 2-3 buds
Distributed along a cordon (cordon training) or around top of the trunk (head training)
Describe replacement cane pruning
Canes are longer sections of one-year old wood - 8-20 buds
Laid down horizontally and need tying to trellis for support/positioning
More complex
Labour intensive
Describe trellising
Trellises are permanent structures of posts/wires that support and position vine’s shoots
Describe untrellised vineyards
Usually head-trained and spur-pruned
Called bush vines
Simple, easy and inexpensive to develop
La Mancha, Spain = beneficial to avoid sunburnt grapes
Not suitable for mechanization
Describe trellised vineyards and 2 types of trellis systems
Shoots can be spread out to maximize light interception, increase air flow, and by positioning fruit in one area, aid mechanization
Vertical shoot positioning (VSP)
Complex training systems
Describe Vertical Shoot Positioning (VSP)
Most common trellising system, most simple
Vine’s shoots trained vertically and held in place onto trellis forming a single narrow canopy
Can be used on head-trained, replacement cane-pruned and cordon-trained, spur-pruned vines
Replacement cane-pruned - called Guyot - one cane (Single Guyot); two canes (Double Guyot)
Best suited to vines with low or moderate vigour
Name the complex training systems
Genevan Double Curtain (GDC) or Lyre - canopy split horizontally
Smart Dyson or Scott Henry - canopy split vertically
List the hazards to vineyards
Drought
Excess of water
Untimely rainfall
Freeze
Frost
Hail
Sunburn
Fire
Smoke taint
Drought management options
Irrigation where permitted
Drought-resistant rootstocks - 110R, 140R
Drought-resistant varieties - Garnacha
Excess of water management options
Plant on slopes
Free-draining soils
Drainage installation
Untimely rainfall management options
Early harvest
Monitor weather forecasts
Choice of site - climate, slope, condition of soil
Freeze management high-level options
Site selection
Choices of varieties
Protecting vines
Freeze management site selection management options
Hillside sites - 5C warmer
Near large/deep bodies of water
Vines planted where snow settles thickly - deep snow can be insulating
Freeze management choice of varieties management options
Resilient to winter freeze - Cabernet Franc, Riesling
Winter hardy American species
American hybrids
Freeze management protecting vines management options
Build up soil around vine graft (hilling up)
Bury vines - extreme climates - China
Prune vines to have several trunks so those killed in winter can be replaced
Describe frost
Frost occurs when cold air below 0C collects at ground level, freezing water in vine’s growing buds and shoots
What are the two types of frost with brief description
Advective - large cold air masses
Radiative - heat evaporation on cool, clear nights
Management options to reduce the risk of frost
Site selection - avoid frost pockets - choose hillside sites where cold air can drain away
Delay pruning postpones budburst into warmer months
Late-budding varieties - Riesling
Train vines high off ground
Have bare soil between vines - absorbs more heat during the day and radiates heat during the night
Management options when frost threatens
Water sprinklers - aspersion - water freezes around parts of plants - releases latent heat, protecting plant
Wind machines
Oil/propane gas burning heaters (smudge pots)
Wax candles (bougies)
Hail management options
Rockets fired into thunderclouds - seed with silver iodide
Net fruit zone
Number of plots in different areas
Crop insurance
Sunburn management options
In designing vineyards - row orientation and aspect reduce impact of hottest afternoon sun
Canopy management - partially shade fruit zone
Agricultural sunscreen spray
Fire management options
Install fire detectors and sprinklers
Install and maintain a water tank
Employee training in event of emergency
Smoke taint management options
Test analytically in days leading up to harvest
Hand harvesting
Gentle or whole bunch pressing
Lower fermentation temps
Reduced maceration times
Flash detente and reverse osmosis - don’t remove taint completely
List pests that can affect vineyards
Phylloxera
Nematodes
Grape moths
Spider mites
Birds
Mammals
What are phylloxera and how is it transported
Aphid-like insect - lays eggs on roots
Transported by air, soil, human activity
Symptoms of phylloxera
Rot spreads through vineyard in increasing sized patches
Leaf galls on underside of leaves
Roots covered with insects surrounded by yellow eggs
Swellings on older roots
Slow, stunted shoot growth
Leaf yellowing around 3 years
Plant dies around 5 years
Management options for phylloxera
Grafting to American rootstocks
Professional advice on choice of rootstock and grape variety to match rootstock to vineyard soil, pests and desired vigour
What are nematodes, the types and how are they spread
Nematodes are microscopic worms
Dagger and root-knot nematodes
Already present in soil, spread by unclean nursery stock, irrigation water and vehicles
Vector for disease - Fanleaf virus - Dagger nematodes
Symptoms of nematodes
Feed on vine roots - reduces yields and vigour
Slow gradual decline
Management options for nematodes
Fumigate soil
Plough in mustard plant - biofumigants
Nematode-resistant rootstocks - Vitis Champini - Ramsey, Dog Ridge
What are grape moths, the types and how are they spread
Light brown apple moth (Australia)
European grapevine moth (southern Europe)
Grape berry moth (central/eastern North America)
Several generations per growing season
Symptoms of grape moths
Feed on flowers and grapes
Wounds created are vulnerable to further attack from bacteria and fungi
Significant crop losses
Management options for grape moths
Biological controls - Bacillus thuringiensis, pheromone capsules, natural predators (parasitic wasps, green lacewings, spiders)
Insecticides
Types of spider mites and how they are spread
Pacific spider mite - most destructive in California
Red spider mites and 2 forms of yellow spider mites - Europe
Symptoms of spider mites
Feed on surface cells of leaves
Discolouration of leaves
Reduction in photosynthesis
Delayed ripening
Reduction in yields
Management options for spider mites
Thrive in dry, dusty conditions
Use water sprinklers and/or cover crops or mulches to reduce dust
Encourage predatory mites
Pesticides
How do birds damage grapevines
Physical damage to grapes
Allows bacteria and fungi to enter bunches - rot
Isolated vineyards at risk
Management options for birds
Netting
Bird scarers, noises - need to rotate noises
Falcons
How do mammals damage grapevines
Eat shoots, leaves and berries
Damage vineyard structures
Management options for mammals
Fencing
Sufficiently high and sunk into soil to stop burrowing animals
List fungal diseases that can affect grape vines
Powdery Mildew
Downy Mildew
Grey rot
Eutypa Dieback
Phomopsis/Cane Leaf Spot
Esca
What fungus causes powdery mildew
Oidium tuckeri
Symptoms of powdery mildew
Attacks young, green parts of vine
Dull grey patches, become black patches as they advance
Damage young shoots, inflorescences, grapes
Reduces yield
Grapes can split at veraison - targets for other infections
Management options for powdery mildew
Open canopy
Sulfur sprays early in season
What fungus causes downy mildew
Peronospora
Symptoms of downy mildew
Yellow, oily circular spots on leaves
Then white, downy fungal growth on underside of leaves
Attacks green parts of plant - young leaves and flowers
Reduces yields by defoliating vine
What conditions does downy mildew thrive in
Warm, humid environments
Rainfall, warm temps - 20C
High risk periods - warm springs and warm/stormy summers
Management options for downy mildew
Copper based sprays - Bordeaux mixture
Fungicides
Good drainage
Open canopy
What fungus causes grey rot
Botrytis cinerea
Symptoms of grey rot
Damage to fruit, flowers and bunches
What conditions does grey rot thrive in
Spores present in vineyard and become active in periods of rainfall and high humidity
What grapes are vulnerable to grey rot
Tight bunches - grapes rub against each other
Punctured by birds/pests
Thin skins
Semillon, Sauvignon Blanc, Pinot Noir
Management options for grey rot
Select less susceptible varieties - small grapes with thick skins - Petit Verdot
Open canopy
Fungicide sprays
Biological control - bacillus subtilis
What is Eutypa dieback and what is another name for it
Fungal trunk disease - rotten wood in vines
Also called dead arm
How is Eutypa dieback spread
Spores spread by wine over long distances
Infections occur through pruning wounds in moderate temps, during rain
Symptoms of Eutypa dieback and susceptible varieties
Stunted shoot growth
Yellow leaves
Susceptible varieties: Grenache, Cabernet Sauvignon, Sauvignon Blanc
Management options for Eutypa dieback
Later pruning
Fungicide application to pruning wounds
Affected trunks - cut back 5-10 cm beyond visible symptoms and treat with fungicides
Dead wood must be burnt
Biological controls - Bacillus subtilis
Retrain from sucker
Remove and replant vine
What is Phomopsis Cane/Leaf Spot and how is it spread
Fungal disease
Causes reduction in yields
In what conditions does Phomopsis thrive?
Prevalent in cool/wet springs followed by humidity and moderate temps
Symptoms of Phomopsis
Infected canes white and break off easily
Shoots growing from these canes develop brown cracks at the base
Leaves also affected
Management options for phomopsis
Fungicides at 3 weeks before budburst and every 2 weeks if wet conditions continue
Remove diseased wood
Early/late pruning in dry weather
Open canopy
What is esca and what conditions is it prevalent in
Esca is a complex fungal disease caused by a group of organisms
Prevalent in warmer/drier climates - southern Europe, California
What is Esca spread
Enters through vine pruning wounds
Symptoms of Esca
Tiger-striping of leaves
Spotting inside wood
Reductions in yield
Death of vine within a few years
Management options of Esca
Disease-free stock
Prune in dry weather
Less detrimental pruning techniques
Promptly remove prunings from vineyard
List the bacterial diseases that can affect grapevines
Pierce’s Disease
Grapevine yellows
How does Pierce’s disease affect grape vines/symptoms
Bacterium lives in sap channels of vines, which it clogs, leading to grape shrivelling
Drop leaves
Death of vine in 1-5 years
Exact symptoms are unclear - vines must be tested in a lab
How is Pierce’s disease spread
Sharpshooter insect - acts as vector - glassy-winged sharpshooter
Management options for Pierce’s disease
No chemical control
Reduce vector opportunities
Strict quarantine rules
Working on Pierce’s disease resistant vines
What is grapevine yellows
Group of diseases caused by bacteria
Flavescence doree - most common in Europe
How is grapevine yellows spread
Bacterial disease is spread by vectors - leafhoppers
Nurseries selling untreated, diseased stock
Symptoms of grapevine yellows
Delayed budburst
Drooping posture because new shoots fail to become woody
Yellow or red canopy
Some strains - vine dies
Other strains - vines can recover
Management options for grapevine yellows
No chemical control
Control vector - leafhoppers - reduced by insecticides
Remove host plant and cover crops
At nursery, bathe pruning wounds in hot water to kill disease
List viruses that can affect grapevines
Fanleaf virus
Leafroll virus
Describe fanleaf virus
Group of diseases (fanleaf degeneration)
Symptoms of fanleaf virus
Early shoot growth stunted
Canes grow in distorted ways
Leaves are very pale, malformed - look like a fan
Cabernet Sauvignon is susceptible
How is fanleaf virus spread
Spread slowly by dagger nematode
Management options for fanleaf virus
No cure - remove and replace affected vines
Before replanting, test soils to check for dagger nematodes
Only virus-tested, clean plantings should be used
Describe leafroll virus
Group of viral diseases widely present around the world
How is leafroll virus spread
Spread by grafting and mealy bugs
Mealy bugs - key pests in South Africa, Mediterranean, Argentina, California
Symptoms of leafroll virus
Slows down growth of roots and shoots
Surviving fruit may take several additional weeks to ripen
Have more acidity, less colour and lower sugar levels
Health of vine affected - stores less carbohydrates
Downward rolling of leaves in autumn
Leaves change colour to red or yellow
Symptoms not always clear - test vines in lab
Some vines/rootstocks carry virus without showing symptoms
Management options for leafroll virus
No cure - remove unproductive vines, replant with virus-free stock
Nurseries scan for virus infections
Open canopies to manage mealy bugs
Natural predators - ladybugs, lacewings
