The Vine & Growing Enviroment Flashcards

1
Q

Name the most common European Vine species

A

Vitis Vinifera

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2
Q

Name the 4 most common American Vine species

A

V. Labrusca,
V.riparia
V.rupestris
V.berlandieri

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3
Q

Name the 7 main components of a vine

A

Leaves, Tendrils, Inflorescences, Lateral shoots, Buds, Main shoot, Trunk

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4
Q

Describe the difference between a compound bud and a prompt bud

A

Compound (latent) buds form in one season and break open the following
Prompt buds form and burst in the same growing season

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5
Q

Name the two types of bud

A

Prompt bud, compound bud

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6
Q

What is a lateral shoots purpose?

A

To allow the vine to keep on growing if the primary shoot is damaged.

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7
Q

What is it called when a lateral shoot inflorences and what variety often produces this?

A

“Second crop” - Pinot Noir

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8
Q

What is the purpose of the tendrils?

A

To allow the vine to support the main shoot, they can be used by growers to attach to a trellis.

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9
Q

What is the purpose of the leaves?

A

To provide the main location for photosynthesis.

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10
Q

Describe transpiration

A

To loss of water through the stomata leading to a water gradient and the vine taking water up through the roots.

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11
Q

Name the grape variety that has a red pulp

A

Alicante Bouschett

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12
Q

Where are the majority of carbohydrates stored in a vine?

A

The trunk and then the roots

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13
Q

Name 2 types of Vine Propgation that produce genetically identical plants.

A

Cutting & Layering

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14
Q

What is the main disadvantage to layering?

A

The vine will grow on its own rootstock

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15
Q

What are the advantages of cutting?

A

Can be done at the same time as other cuttings
Permits the use of rootstock
cuttings can be treated by nurseries

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16
Q

How do clones arise?

A

Clones arise due to genetic mutation at cell division.

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17
Q

What are the advantages and disadvantages of buying from a nursery?

A

Free from disease
Growth can be uniform and simpler to manage

Could be a limit of clones available
Could lead to a lack of diversity and complexity
Diseases and pests could become more dangerous

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18
Q

What is mass selection?

A

Mass selection is when growers use their own cuttings and cultivate from those. They are generally the best performing vines and are chosen after years of monitoring.

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19
Q

Define a cross

A

A cross is a new vine from 2 parent vines of the same species

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20
Q

Define a hybrid

A

A hybrid is a new vine from 2 parent vines of different species

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21
Q

What does a vine need and what are the adverse conditions during Dormancy?

A

Vine needs temps below 10 degrees

Extremely cold temps -20
Unusually mild temps

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22
Q

Name a variety that is winter hardy?

A

Vidal (lesser riesling)

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23
Q

What does a vine need and what are the adverse conditions during Budburst

A

Air & Soil temp > 10 degrees

Frost
Cold soils

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24
Q

Varieties that require lower temperatures to bud are called what? Name a variety

A

Early budding - Merlot (chard, pinot noir, grenache)

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25
Q

Varieties that require higher temperatures to bud are called what? Name a variety

A

Late budding - Ugni Blanc ( Sauv B, Syrah, Cab Sauv)

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26
Q

What can be done in the vineyard to delay budburst?

A

Late winter pruning

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27
Q

What does a vine need and what are the adverse conditions during Shoot & Leaf Growth

A

Stored carbohydrates
Warmth, sunlight, nurtrients, water

Low carb levels (poor previous season)
Water stress
Dry soils limiting nutrient uptake

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28
Q

What does a vine need and what are the adverse conditions during Flowering & Fruit Set

A
Warm temps (min 17 degrees)
Sun, warmth, water, nutrients for fruitfullness next season

Rainy
cloudy
windy
cold temps

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29
Q

Briefly describe pollination in a vine

A

Pollination is the process of pollen falling from the stamen on to the stigma. This will form a pollen tube that will penetrate the stigma, the ovary and then the ovule where it will fertilise the egg with sperm cells.

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30
Q

The stamen is made up of what two parts?

A

The anther and the filament

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31
Q

What will the fertilised egg become?

A

The seed of a grape.

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32
Q

What is the range of percentage of successful flowerings and most common percentage

A

0-60% Typically 30%

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33
Q

Why are windy, rainy and cold weather bad at fruit set?

A

Can disrupt pollen tube growth (lead to coulure)

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34
Q

Name 2 negative conditions that can arise from fruit set

A

Coulure & Millerandage

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35
Q

Describe Coulure and why it is caused. Name a variety susceptible

A

Coulure is a condition where fruit set has failed for a high percentage of flowers. It is caused due to an imbalance in carbohydrate levels, low rates of photosynthesis & very fertile soils.

Grenache, Cab Sauv, Merlot, Malbec

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36
Q

Describe Millerandage and why it is caused. Name a variety susceptible

A

Millerandage is a condition where there is a high proportion of seedless grapes within a bunch. They will be smaller and can affect yields. It is caused due to wet windy cold weather

Chardonnay & Merlot

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37
Q

What does a vine need and what are the adverse conditions during Grape Development

A

Sunlight, warmth, mild water stress

Too much water & nutrients
Excessive shading
Very cold or Very hot conditions

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38
Q

Name the 4 stages of grape development

A

Early grape growth
Veraison
Ripening
Extra Ripening

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39
Q

Briefly describe early grape growth

A

Hard green grapes grow and malic tartaric acids accumulate. Sugar levels are low, tannins begin to accumulate. Some aromas and precursors develop. Milld water strees encourages grape growth over vegetitive growth.

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40
Q

Briefly describe Veraison

A

Grape growth slows for a few days (lag phase). Grape cell walls become stretchy and supple. The synthesis of anthocyanins starts as chlorophyll is broken down. Black varieties start to become red and white become slightly translucent.

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41
Q

Briefly describe Ripening

A

Vegetative growth has slowed drastically. Cells expand rapidly with the accumulation of sugar, acid drops. Tannins and anthocyanins continue to develop. Sugar accumulation is rapid to begin with and then slows. Max rate at 18-33 degrees and 1/3 sunshine.

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42
Q

What are the tubes called that transport water and suagr respectively

A

Xylem & Phloem

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43
Q

At what point are tannins at their highest during grape growth?

A

Veraison

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44
Q

Length of ripening is based on ___ (4 points)

A

Grape Variety, climatic conditions, management of the vine and vineyard, time of harvest.

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45
Q

How much sunlight does a vine typically need?

A

1/3 of full sunshine

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46
Q

Sunlight enhances what in the grape ____ (4 points)

A

development of anthocyanins
reduction of methoxypryrazines
developing tannins pre veraison
polymerisation of tannins post veraison

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47
Q

Between what latitudes will grapes typically grow?

A

30 - 50 degrees north and south of equator

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48
Q

Explain why vineyards at higher latitudes receive less sunlight when all other factors are equal

A

The sun hits these regions at a lower angle and the sunlight has to pass through more of the atmosphere.

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49
Q

What is the temperature drop for every 100m about sea level?

A

0.6 degrees C

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50
Q

Explain why sunshine is more intense at higher altitudes

A

It has to go through less atmosphere

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51
Q

Higher altitude areas are thought to have a higher or lower dinural range compared to lower sites?

A

They are thought to have a higher range as there is less atmosphere to moisture so the heat is quickly dissipated.

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52
Q

Describe the importance of aspect in relation to latitude

A

Areas of high latitude can use slopes to increase the volume of light received in a vineyard by increasing the angle at which it hits the land while lower latitudes can use aspect to face the vineyard away from the sun and receive less of the suns rays.

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53
Q

Describe the important of east of west facing vineyards in terms of solar radiation

A

Vineyards that face the east can benifet from the morning sun and can extend hours of vine growth in cooler climates.

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54
Q

Why do large bodies of water regulate temperature and sunlight of nearby land? (2 points)

A

Large bodies of water take longer to heat up and longer to cool down. During the day the cold air is drawn to the land and helps cool it down. It retains heat better than the land so at night it will slowly release the heat.

The water will help reflect sunlight and is more noticeable at higher latitudes with steep slopes

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55
Q

Give an example of a cool & warm climate that uses a body of water to regulate temperature

A

Finger lakes NY

Carneros CA

56
Q

In relation to current why can California grow cool climate grapes?

A

The California current that comes from the west is a cold current and can regulate the temperature

57
Q

In relation to current why can Bordeaux grow warm/hot climate grapes?

A

The warm gulf stream heats up bordeaux and allows these varieties to ripen.

58
Q

What is ENSO

A

El Nino - Southern Oscillation

59
Q

Describe El Nino and then say why

A

Warm water moves eastward in the Pacific Ocean causing increased rainfall & hurricanes in S.America. It brings warmer drier conditions to the north. Causes warmer drier conditions in western Aus. Happens every 3-7 years. El Nina contributes the opposite by cold water moving east.

60
Q

How can wind affect climate and the vineyard? 5 points

A

Can have a warming or cooling influence
Valleys can act as funnels for the wind
Winds that travel across hot land masses can heat up the vineyard (Zonda Mendoza)
Increases evapotranspiration
Wind that is strong can damage fruit of vines and lower yields

61
Q

Describe the importance of coloured soils

A

Dark soils such as those heavy with gravel or black (etna) will retain heat much better and will radiate it back into the vine at night. This can be good for late ripening varieties. Light coloured soils are much better at reflecting solar energy, this can be utilised in cooler climates to gain more sunlight for the under canopy.

62
Q

Why are stoney soils suitable for cooler climates?

A

Stoney soils heat up faster than tight soils that retain water well and can help to stimulate bud break.

63
Q

Describe how fog can affect an area

A

Fog can be useful to reduce temperature but must have ample sunlight to burn it off
Prolonged fog can affect photosynthesis
In areas of fog there is increased risk of fungal disease like noble rot.

64
Q

What is the minimum requirements of water for a cool and warm climate?

A

500mm cool - 750mm warm.

65
Q

Why does a vine need water? 4 points

A

Photosynthesis
turgidity
regulating temperature
uptake of nutrients

66
Q

Name 3 types of water source

A

Rainfall
Irrigation
Water table

67
Q

Define evapotranspiration rate

A

Evapotranspiration rate is the amount of transpiration from the vine combined with the evaporation of water from the soil surface.

68
Q

What factors effects evapotranspiration rate?

A

temperature, humidity & wind. Hot dirier windier areas have a higher rate.

69
Q

Name the 5 main nutrients that a vine needs

A
Nitrogen,
Phosphorus
Calcium
Potassium
Magnesium
70
Q

Describe the role of nitrogen and result of excessive and scarcity.

A

Essential for vine growth and impact on vigour & grape quality.
Too much - Excess Vigour
Too little - Problems with fermentation

71
Q

Describe the role of Potassium and result of excessive and scarcity.

A

Essential for vine growth and flow of water
Too much - reduced uptake of magnesium, reducing yields and ripening
Too little - Low sugar accumulation

72
Q

Describe the role of Phosphorus and result of scarcity.

A

Important for photosynthesis

Too little - Poorly developed root systems

73
Q

Describe the role of Calcium and result of scarcity.

A

Important for structure of plant cells and photosynthesis

Too little - Rare but can effect fruit set

74
Q

Describe the role of Magnesium and result scarcity.

A

Found in chlorophyll and has a key role in photosynthesis

Too little - Reduced yields and poor ripening

75
Q

What is One-Year-Old Wood & Permanent Wood? (apart from the obvious!)

A

O-Y-O Wood = The shoots from the previous growing season that were not removed at pruning.

Perm. Wood = Woody parts of the vine that are older than one year. One or more horizontal arms called ‘cordons’.

76
Q

Name the components of the grape. (7)

A
  1. Water
  2. Sugar
  3. Acids
  4. Colour
  5. Tannin
  6. Aroma compounds
  7. Aroma precursors
77
Q

Name the 9 steps of the vine’s Growth Cycle.

A
  1. Dormancy
  2. Budburst
  3. Shoot and Leaf growth
  4. Flowering
  5. Fruit set
  6. Grape berry formation
  7. Veraison
  8. Ripening
  9. Extra-ripening
78
Q

What factors affect temperature and sunlight? (9)

A

Latitude, altitude, slopes and aspect, proximity to water, winds, characteristics of the soil, clouds, mist and fog, diurnal range.

79
Q

What factors affect water availability? (3)

A

Rainfall, characteristics of the soil and land, evapotranspiration rate.

80
Q

What factors affect nutrient availability? (4)

A

Factors that affect water availability, soil pH, soil health, characteristics of the soil and land.

81
Q

Define diurnal range.

A

The difference between day and night temperatures.

82
Q

What is a cool climate? (and give an example) (2)

A

Less than 16.5’C

England

83
Q

What is a moderate climate? (and give an example) (2)

A

16.5’C - 18.5’C

Northern Rhone

84
Q

What is a warm climate? (and give an example) (2)

A

18.5’C - 21’C

?

85
Q

What is a hot climate? (and give an example) (2)

A

21’C +

La Mancha

86
Q

Define a Continental climate (and give an example).

A

Far away from any large body of water, high diurnal range, more extreme differences between summer and winter temperatures, short summers and cold winters.

E.g. Alsace

87
Q

Define a Maritime climate (and give an example).

A

Less distinct seasons, rains throughout (evenly spread throughout the year), longer growing season.

E.g. Bordeaux

88
Q

Define a Mediterranean climate (and give an example).

A

Low annual difference between summer and winter temperatures. A bit like a warm maritime climate. Mild winters. Tends to rain in winter, giving dry summers.

E.g. Coonawara

89
Q

What are the threats and opportunities posed by climate change?

A

Threats - each stage of vine cycle speeding up (acidity down, ripeness and alcohol up), style of wines jeopardised (e.g. Champagne & Northern Rhone black pepper), hotter in already hot climates (Barossa Valley - unbalanced wine).

Opportunities - greater evapotranspiration & water stress (make vine work harder), good for places where it’s been too cold (e.g. Tasmania and South England).

90
Q

What 9 potential hazards are there?

A
  1. Drought
  2. Excess of water
  3. Untimely rainfall
  4. Freeze
  5. Frosts
  6. Hail
  7. Sunburn
  8. Fire
  9. Smoke taint
91
Q

Why is Drought a problem, and how can it be managed?

A

Problem - affect quality & quantity, close stomata, stop photosynthesis, reduced grape size & slow ripening, vine shut down (die).

Management - irrigation (v. expensive), drought-resistant rootstocks and varieties, don’t plant vines too close.

92
Q

Why is Excess of Water a problem, and how can it be managed?

A

Problem - encourage vegetative growth (compete for vine’s sugars), too much shading (reduced tannins and aroma compounds), poor ventilation (fungal diseases), damp soils cold (delay budburst, shorten growing season), waterlogging.

Management - drainage systems, slopes, water-tolerant rootstocks.

93
Q

Why is Untimely Rainfall a problem, and how can it be managed?

A

Problem - during pollination and fruit set = millerandage or coulure (lower yield & quality), during summer = reduce rate of ripening, close to harvest = diluting must, grapes splitting (grey rot).

Management - pick grapes early (affect style of wine)

94
Q

Why is Freeze a problem, and how can it be managed?

A

Problem - temp. below -20’C = vine damaged or killed.

Management - better site selection (hillside, large bodies of water, thick snow - insulate vine). winter-hardy variety (Riesling), hardy species (Vitus Amurensis). Burners, sprinklers (aka. aspersion system), turbines. Several trunks (back up)

95
Q

Why is Frost a problem, and how can it be managed?

A

Problem - cold air below 0’C collects at ground level, freezing water in growing buds and shoots.

Management - better site selection (hillside, avoid frost pockets), delaying pruning, high-trained vines, bare soil (absorbs heat, radiates back at night). Water sprinklers,, wind machines, oil burning heaters.

96
Q

Why is Hail a problem, and how can it be managed?

A

Problem - rip young shoots and leaves, damage ripening grapes (susceptible to grey rot), reduce yields (then & later harvests).

Management - rockets (turn hail to rain 🤨), net fruit, have different locations.

97
Q

Why is Sunburn a problem, and how can it be managed?

A

Problem - scars on grapes, browning (bitter flavours), increase susceptibility to rot.

Management - selective picking, canopy management, additional irrigation, sunscreen.

98
Q

Why is Fire a problem, and how can it be managed?

A

Problem - damage to property, irrigation systems, trellising, vine, smoke-taint.

Management - fire detectors, sprinklers, water tank, employee training, praying.

99
Q

Why is Smoke Taint a problem, and how can it be managed?

A

Problem - sticky (sticks to bloom), smoky, rubbery flavours to grape, aroma compounds absorbed (increase during ageing).

Management - blending, hand-harvesting, lower fermentation temps., reduced maceration time, flash detente, fire barriers (trees, mounds).

100
Q

What is Phylloxera?

A

Insect. Lays egg on roots. Spreads through crawling and by humans. Identified in Europe in 1863.

101
Q

Why is Phylloxera a problem, and how can it be managed?

A

Problem - reduces uptake of water and nutrients. Leaves roots susceptible to further attack. Vine dies after 3-5 years.

Management - American vine species (V. Berlandieri - form hard, corky layers that surround eggs, seal wounds). Phylloxera rootstocks (clogs mouth & it dies 💀)

102
Q

What are Nematodes?

A

Microscopic worms. Important for soil health. Most common = root-knot and dagger.

103
Q

Why are Nematodes a problem, and how can they be managed?

A

Problem - feed on growing roots. Reduce yields. Viral diseases.

Management - clean and healthy nursery equipment, mustard plant cover-crop, nematode resistant rootstocks (e.g. Ramsey), fumigate soil.

104
Q

What are Grape Moths?

A

Moths that eat the green parts of vine and grapes. E.g. Grape Berry Moth (Central and Eastern North America)

105
Q

Why are Grape Moths a problem, and how can they be managed?

A

Problem - feed on flowers and grapes. Vulnerable to attack from bacteria and fungi.

Management - Bacterium (bacillus thuringiensis) - toxic, theramone traps (emits sexual chemical that confuses them), natural predators, insecticides.

106
Q

What are Spider Mites?

A

Spiders that feed on surface cells of leaves. E.g. Pacific spider mite in California.

107
Q

Why are Spider Mites a problem, and how can they be managed?

A

Problem - discolouration of leaves, reduced photosynthesis, delayed ripening, lower yields.

Management - predator (other spider mites eat spider mites), wet, humid conditions (water sprinklers), cover crops (reduce dust), pesticides.

108
Q

Why are Birds a problem, and how can they be managed?

A

Problem - destroys entire crops, physically damage grapes, susceptible to rot.

Management - nets, scarers, predatory birds (e.g. Falcons).

109
Q

Why are Mammals a problem, and how can they be managed?

A

Problem - eats shoots, leaves, and grapes. Damage grapes so susceptible to rot, damaging trellising, reduce yield, lower quality, increase costs.

Management - a (well-measured) fence.

110
Q

What is Powdery Mildew?

A

A fungal disease caused by the fungus Odium Tuckeri. Introduced to Europe - mid 1800’s. Now - one of the most widespread vine diseases around world. Chardonnay & Cab Sav susceptible.

111
Q

Why is Powdery Mildew a problem, and how can it be managed?

A

Problem - attacks young green parts of vine. Reduces yields. Slows photosynthesis down. Thrives in shady conditions.

Management - open canopy, sulfur, systemic fungicides, improve drainage, easier to prevent than contain.

112
Q

What is Downy Mildew?

A

Caused by Peronspora (water mould that lives within vine tissue). Introduced from N. America (late 1800s).

113
Q

Why is Downy Mildew a problem, and how can it be managed?

A

Problem - attacks green parts of vine. Reduces yields. Slows photosynthesis. Needs rainfall & warm temps. Yellow ‘oil’ spots.

Management - copper sprays, fungicides, good drainage, open canopy.

114
Q

What is Grey Rot?

A

a fungus aka. Botrytis Cinerea that damages fruit.

115
Q

Why is Grey Rot a problem, and how can it be managed?

A

Problem - loss of yield, drop of quality, vulnerable if grapes have point of entry, tight bunches with thin skins susceptible (Pinot Noir). Active in rainfall & high humidity.

Management - small grapes, thick skinned varieties (Petit Verdot), protecting grapes from other pests, open canopy, fungicides, antagonistic bacteria.

116
Q

What is Eutypa Dieback?

A

aka. Dead Arm. A fungal trunk disease, leading to rotten wood.

117
Q

Why is Eutypa Dieback a problem, and how can it be managed?

A

Problem - reduces yields, kills vines over 10-year period (if not tackled). Spores spread by wind. Grenache susceptible. Mainly South Australia, south-west France & California.

Management - pruning late, applying fungicide to pruning wounds, affected wood cut back beyond visible symptoms, dead wood burnt, biological controls.

118
Q

What is Phomopsis Cane and Leaf Spot?

A

A fungal disease where canes whiten and develop brown cracks.

119
Q

Why is Phomopsis Cane and Leaf Spot a problem, and how can it be managed?

A

Problem - reduces yields, cool & wet springs followed by humidity, Grenache susceptible.

Management - fungicides (applied 3 weeks after budburst), diseased wood removed at pruning, improve air flow.

120
Q

What is Esca?

A

A fungal disease. Caused by a group of organisms. Southern Europe and California. Symptom = tiger-striping of leaves, spotting inside wood.

121
Q

Why is Esca a problem, and how can it be managed?

A

Problem - reduces yields. Death within a few years.

Management - no treatment, so must be prevented. Clean nursery equipment. Steaming canes at 100’C to kill bacteria, fungicide, creating less humid conditions.

122
Q

What is Pierce’s Disease?

A

A bacterial disease. Kills vines. Originated on American continent. Spread by sharpshooter insect. Chardonnay susceptible.

123
Q

Why is Pierce’s Disease a problem, and how can it be managed?

A

Problem - lives in sap channels, clogs it, grapes shrivels. Death of vine between 1-5 years.

Management - reducing number of sharpshooters, quarantine, future work on Pierce disease resistant rootstock.

124
Q

What is Grapevine Yellows?

A

A group of diseases caused by a type of bacteria. No treatment. Spread by vectors (leafhoppers) and unclean nursery equipment. Symptoms - delayed budburst, dropping posture, yellow or red canopy. Riesling susceptible.

125
Q

Why is Grapevine Yellows a problem, and how can it be managed?

A

Problem - Drastically reduces yield and lowers quality.

Management - no control, controlling the vector, clean nursery equipment.

126
Q

What is Fanleaf Virus?

A

A group of viral diseases. Around the world. Early shoot growth stunted, canes distorted, leaves pale & malformed (fan-looking). Cab Sav susceptible. Spread - unclean nursery equipment & dagger nematode.

127
Q

Why is Fanleaf Virus a problem, and how can it be managed?

A

Problem - effects vary (from little effect to losing most of the variety).

Management - no cure, removing and replacing vines, virus-tested, clean nursery equipment, no dagger nematodes in soil.

128
Q

What is Leafroll Virus?

A

Group of viral diseases. Around the world. Spread by grafting & mealy bugs. Slows down growth of roots & shoots. Downward rolling of leaves.

129
Q

Why is Leafroll Virus a problem, and how can it be managed?

A

Problem - compromises photosynthesis. Does not kill vine, but reduce yield up to half, affects quality - more acidity, less colour, less sugar.

Management - no cure, remove unproductive vines and replant, screen vines, healthy and clean nursery equipment, open canopy.

130
Q

What is a Cutting (and an advantage)?

A

A section of vine shoot that can be planted and will then grow as a new plant.

Adv. - many can be propagated at same time, permits rootstocks.

131
Q

What is Layering (and an advantage and disadvantage)?

A

Using shoots from an established neighbouring vine to produce a new vine. A cane is bent down, and a section buried. The tip points out of the ground. Section takes root. Roots establish. Cane cut.

Dis. - grows on its own roots. Susceptible to phylloxera. No choice of variety.

132
Q

Define Growing Degree Days (GDD)

A

Model of heat summation created by Armeire and Winkler (1944) intended for use in California

133
Q

List the steps in how GDD is calculated

A
  1. For celcius, subtract 10 from the average mean temp in a month of the growing season.
  2. Multiply this by number of days in that month.
  3. Do for all growing months and add together to give GDD.
134
Q

Describe the Huglin Index

A

Created by Huglin (1978) which uses a similar formula to GDD but takes into account both mean and max temperatures and increased day length at higher altitudes. Varieities are mapped to each band and is widely used in Europe.

135
Q

Describe Mean Temperature of Warmest Month (MJT)

A

Created by Smart and Dry (1980), uses mean temp of July (Northern H) or January (Southern H) as well as continentality, humidity and hours of sunlight. It is split into 6 bands.

136
Q

Describe Growing Season Temperature

A

Closely related to GDD and is easier to calculate. It uses mean temp of whole growing season and is split into bands.