Unit 1 Viticulture- The Growing Environment Flashcards
What is the basic building block of the vine?
Glucose
What is the photosynthesis equation for a vine?
Sunlight+water+CO2–chlorophyll= glucose
At what temp and below is the vine dormant?
10C
At what temp does vine growth peak?
22-25C
What is the average temp in a cool, moderate, warm and hot climate?
Cool- Below 16C
Moderate- 16.5-18.5C
Warm- 18.5C-21C
Hot- Over 21C
Give examples of cool, moderate, warm and hot regions
Cool- Champagne, Mosel, Southern England, Anderson Valley, Tasmania
Moderate- Bordeaux, N Rhone, Rioja, Piedmont, Tuscany, Coonawarra, Marlborough, Napa/Sonoma
Warm- S Rhone, Douro, Jerez, McLaren Vale, Paarl
Hot- San Joaquin Valley CA
What is a maritime climate and give examples
Low range of temps, high rainfall, near large bodies of water
Bordeaux, Muscadet, Rias Baixas, Vinho Verde
What is a mediterranean climate and give examples
Low range of temps, mild winters, dry summers and most rain falling during the winter
West Coast US, Childe, SE Australia, Cape in SA
What is a continental climate and give examples
Wide range of temps- hot summers cold winters, inland
Champagne, Mendoza, central spain, Germany
What is an example of a tropical climate?
India and Brazil- no dormant period, vines not as productive
What are the 4 main advantages of having a body of water near a vineyard site?
- Reflect sun’s rays
- Provide source for irrigation
- Reduce risk of ground frost
- Provide morning mists to develop noble rot
What fungal disease is more common in vineyards near bodies of water?
Downy mildew
What negative effects can a thick canopy have?
- reduce flower initiation and berry set
- higher levels of acid retention in grapes
- reduce sugar accumulation
- encourage competition between shoot tips and berries for sugar which reduce berries ability to ripen
At what temp does injury to dormant vines begin, and what temp is a site unsuitable for vines?
-15C, -20C (or if mean temp for a month is less than -1C)
What is the problem with the heat summation system?
Relationship between between vine growth and temp is not linear- it slows down when temps are above 30C
What are the main trends as the region gets warmer in the EU Zones A to C?
- min potential alcohol requirement increases
- level to which must can be enriched decreases
- deacidification becomes illegal, acidification becomes legal
How does vine density affect how much precipitation is needed?
The higher the density, the more precipitation is needed
In what climate is it important that soil can retain water?
Mediterranean- because most rain falls in winter
What three regions are prone to hail?
Mendoza, Piedmonte, Burgundy
How does high rainfall affect the berries?
- can cause fungal disease
- reduce fruit set
- cause bunch compaction and berry splitting,
- dilute berries if before harvest
Why can it be beneficial to have increased lear area and canopy in cool temps?
Because the rate of photosynthesis slows, and it takes a larger leaf area to ripen fruit
What time is leaf removal around the fruiting zone commonly practiced and why?
Several days before harvest to ensure full ripening while minimizing burn risk
What is the relationship between the amount of sugar in a grape and heat vs sunlight?
Sugar increases with photosynthesis from sunlight, while other metabolic needs increase with temperature. In hot, cloudy conditions like Hunter Valley sugar is low while in cool, sunny conditions sugar can be high (Alsace)
How many hours are needed to produce ripe fruit in vitis vinifera?
1250 hrs
Why do wines grow best on soils with low fertility?
- restrict canopy growth
- are often stony and well drained
Arrange in line from smallest to largest diameter:
Fine sand, sand clay, gravel, and silt
Clay, silt, fine sand, sand, gravel
What soil retains the most moisture?
Clay, because it is made up of very small particles
What is the ideal soil texture and why?
Loam, balanced mix of clay, silt and sand. They combine nutrient holding abilities of clay with the good drainage of sand
How is limestone formed?
Through the deposition of shells and skeletons of marine animals. Consists of calcium carbonate and is alkaline and free draining
How is granite formed?
By solidified magma produced by volcanoes.
What is humus?
Decomposed organic matter
What is the minimum amount of water vines need during the growing season?
500 mm
What can aeration do to the soil?
Provide oxygen to aerobic organisms, removes CO2, provides roots with oxygen
How can soil compaction affect the vineyard?
Poor rain infiltration, poor soil structure, reduced drainage, aeration, and root penetration
What are the major elements of soil?
Nitrogen Phosphorous Potassium Calcium Sulfur Magnesium
What are minor or trace elements of soil?
Boron Manganese Copper Iron Molybdenum Zinc, Cobalt Chlorine Silicon
What element is an essential component of chlorophyll ?
Magnesium
What element regulates cell acidity and is an important component of cell walls?
Calcium
What element regulates the flow of water and sugar in the plant?
Potassium
What element is key in energy fixation, root growth and ripening?
Phosphorous
What type of growing conditions for vines produce the best fruit?
Densely planted, small vines, growing on infertile soils
What is the lowest pH you can grow a vine in?
5
