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Question-Where are carbohydrates stored in a vine? - Answer-Stems, trunks, roots Question-Define lignify - Answer-Green shoots become woody and rigid, they are then called canes Question-Where do buds form? - Answer-between the leaf stalk (petiole) and the stem Question-Define the two types of buds - Answer-- Compound buds (form in one growing season and break open the following growing season, producing main shoots; typically a primary, secondary, and maybe tertiary)- Prompt buds (form and break open same season, form lateral shoots)
- Prompt buds (form and break open same season, form lateral shoots) Question-What is the main function of lateral shoots? When are they desirable/undesirable? - Answer-- to allow the plant to carry on growing if the tip of the main shoot has been damaged or eaten
- can provide an additional source of leaves for photosynthesis (useful if the laterals are near the ends of the main shoots) Question-What is second crop? - Answer-Lateral shoots often produce inflorescences, which can be known as a 'second crop'
- Growth of laterals nearer the base of the main shoot can be undesirable as they impede air flow and can shade the fruit too much
Question-What is green harvesting? - Answer-Removal of second crop during summer Question-Define one-year-old wood - Answer-the main shoots from the last growing season that were kept at pruning, supports compound buds; cane or spur Question-Define permanent wood - Answer-woody parts of the vine that are older than one year, including the trunk Question-where are most roots found? - Answer-top 50cm of soil Question-Most important North American grape species - Answer-Vitis labrusca, Vitis riparia, Vitis berlandieri and Vitis rupestris Question-Four main sections of a grape vine - Answer-the main shoots, one-year-old wood, permanent wood and the roots Question-What comprises the canopy of a vine? - Answer-The main shoots and all of their major structures - stem, buds, leaves, lateral shoots, tendrils and inflorescences/grape bunches Question-What do the main shoots grow from, and when? - Answer-The main shoots on the vine grow in spring from buds retained from the previous year Question-what distinguishes PN clone 115? - Answer-low yield, small grapes, good for high quality of red wines Question-what distinguishes PN clone 521? - Answer-high yield, bigger grapes, good for sparkling wine production Question-When is leaf fall and dormancy? - Answer-Nov-March Question-When is budburst? - Answer-March-April
Question-what can slow initial shoot growth rates? - Answer-low carb levels Question-what supports shoot growth in later stages? - Answer-photosynthesis Question-at what point of the vine growing cycle is water stress not desired? - Answer-late stages of shoot growth (can affect photosynthesis) Question-what can stunted shoot growth lead to? - Answer-- weak shoots
- reduction in leaf number/smaller leaves
- inflorescences that do not flower properly Question-what can limit bud fruitfulness? - Answer-- low temp (<25C)
- water stress
- shading
- nutrient deficiency Question-how long after budburst does flowering typically take place? - Answer-8 weeks (temp dependent) Question-why are warm conditions (>17C) desired during flowering? - Answer-speeds up flowering (occurs within a few days) Question-what % of flowers become grapes typically? - Answer-30% Question-what temp does pollen germination require? - Answer- 26 - 32C Question-what negatively affects pollen tube growth? - Answer-wind, rain, cold temps; wind, water stress, hot temps
Question-define coulure - Answer-A condition of the grape bunch in which fruit set has failed for a high proportion of flowers. This occurs when ovule fertilisation is unsuccessful, and therefore no grape develops. Question-what causes coulure? - Answer-imbalance in carb levels due to:
- low photosynthesis rates
- vigorous shoot growth diverting carbs (very fertile soils, vigorous rootstocks) Question-define millerandange - Answer-A condition of the grape bunch in which there is a high proportion of seedless grapes. Question-what causes millerandange? - Answer-cold, wet, windy weather at pollination and fruit set Question-what elements develop in grapes during stage 1 of grape formation and development? - Answer-- tartaric and malic
- some aroma compounds and aroma precursors (methoxypyrazines)
- tannins (promoted by sunshine on grapes - sunscreen) Question-during stage 1 of grape formation and development sugar levels are ______, water flow is _______ & provided by the ________. - Answer-- low
- high
- xylem Question-too much _________ & __________ can prolong stage 1 of grape formation and development because _____________. this can delay _____________. - Answer-- water
- nitrogen
- these will encourage shoot growth instead
- onset of the ripening stage
Question-what happens during grape ripening? - Answer-- cells expand rapidly
- sugar and water accumulate
- acid levels fall (respiration of malic acid) Question-at what temp does photosynthesis take place at a max rate? at what sunlight levels? - Answer-- 18 - 33C
1/3 full sunshine Question-where does sugar come from during ripening? - Answer-- sugar solution from phloem (sugars from photosynthesis)
- reduction in water (xylem flow stops, water is transpired through grape skins) Question-Mean temperatures above ____________ in the final month of ripening can lead to a rapid loss of acidity - Answer-21C (70F) Question-mean temperatures below ____________ can reduce acid loss to a point that acidity levels in the must are too high - Answer-15°C (59°F) Question-what aromas do terpenes give? - Answer-floral, citrus, grapey Question-Chardonnay shows aromas of _____________ in cool climates and ____________ in warm climates - Answer-- green and citrus fruit
- stone fruit and tropical fruit Question-levels of tannins are __________ at véraison and ____________ slightly throughout ripening because __________________ - Answer-- high
- decrease
- tannins polymerise (this causes them to become less bitter) Question-anthocyanins increase most rapidly at temps between _______ and _______ - Answer- 15C and 25C
Question-The length of the ripening stage will depend on: - Answer-- variety
- climatic conditions
- vine & vineyard management
- time of harvest Question-what is stage 4 of grape growth and ripening? - Answer-extra ripening Question-what happens during stage 4 of grape growth and ripening? - Answer-- No more sugar or water are imported to the grape by the phloem at this stage, but water loss in the grape through grape transpiration means that sugars are concentrated
- Extra-ripe aromas can also develop Question-what is the ideal temp range for fruit set? - Answer- 26 - 32C Question-what factors affect temp and sunshine levels? - Answer-- latitude
- altitude (& diurnal range)
- slope, aspect
- proximity to water
- wind
- soil characteristics
- mist, fog, clouds Question-temp falls by ________ for every 100 m increase in altitude - Answer-0.6C/1.1F Question-Generally, the vine needs a minimum of ______ mm of rainfall per year in cool climates and at least ______ mm in warm regions - Answer- 500 750
Question-why do vines need phosphorous? what are the effects of too little? - Answer-- important for photosynthesis
- low: poorly developed root systems, reduced vine growth, lower yield Question-why do vines need calcium? what are the effects of too little? - Answer-- needed for structure of cells, photosynthesis
- low: poor fruit set Question-why do vines need magnesium? what are the effects of too much/too little? - Answer-- found in chlorophyll
- low: reduced yield, poor ripening Question-how does soil pH affect nutrient availability? - Answer-Different nutrients become more or less available at different pH levels. For example, iron is poorly available in soils with high pH (e.g. soils with a high proportion of calcium carbonate such as limestone) and this can cause chlorosis. Question-define climate - Answer-the annual pattern of temperature, sunlight, rainfall, humidity and wind averaged out over several years (30 years in the timescale generally agreed) Question-define the GDD model - Answer-- For Celsius, subtract 10 (the temperature in Celsius below which vines cannot grow) from the average mean temperature of a month in the growing season. For Fahrenheit, subtract 50 (the temperature in Fahrenheit below which vines cannot grow) from the average mean temperature (in Fahrenheit) of a month in the growing season.
- multiply this by the number of days in that month
- make the same calculation for each month in the growing season (April to October in the Northern Hemisphere, October to April in the Southern Hemisphere) and add together the totals to get the GDD. (Any months with a negative value would not be counted.) Question-define maritime climate & give an example - Answer-low annual differences between summer and winter temperatures. Rainfall is also relatively evenly spread throughout the year. An example of a maritime region is Bordeaux.
Question-define mediterranean climate & give an example - Answer-low annual differences between summer and winter temperatures. The annual rainfall tends to fall in the winter months, giving dry summers. Examples include Napa Valley and Coonawarra. Question-define continental climate & give an example - Answer-more extreme differences between summer and winter temperatures. They often have short summers and cold winters with temperatures rapidly changing in the spring and autumn. Examples include Burgundy and Alsace. Question-define cool climate - Answer-regions with an average GST of 16.5°C (62°F) or below Question-define moderate climate - Answer-regions with an average GST of 16.5-18.5°C (62- 65°F) Question-define warm climate - Answer-regions with an average GST of 18.5-21°C (65-70°F) Question-define hot climate - Answer-regions with an average GST in excess of 21°C (70°F) Question-define continentality - Answer-a measure of the difference between the annual mean temperatures of the hottest and coldest months Question-define the GST model - Answer-(Growing Season Temperature) This model uses the mean temperature of the whole growing season and, again, these temperatures are grouped into climatic bands ranging from cool to hot. It is very closely correlated to GDD and is easier to calculate. Question-define weather - Answer-annual variation that happens relative to the climatic average Question-what is integrated pest management also known as? - Answer-lutte raisonee Question-define conventional viticulture - Answer-- mechanization
Question-what are the advantages of organic viticulture? what are the disadvantages? - Answer-- health of vines & soil, disease resistance, reduction of chemical treatments, cost savings on synthetic chemicals
- lower Y, significantly lower Y in difficult years, more reliance on copper sprays, cost and time spent on certification Question-whose work is biodynamic viticulture based on? - Answer-Rudolf Steiner & Maria Thun Question-what is Preparation 500? - Answer-Horn Manure: cow manure in put into a cow's horn & buried, then dug up and the contents are "dynamised" (stirring the contents of the horn into water (creating a vortex and then reversing it) so that the water memorizes the power of the preparation), then sprayed onto the soil as a homeopathic compost Question-what is Preparation 501? - Answer-Horn Silica: cow's horn filled with ground quartz (silica) and buried, then dug up, dynamised and sprayed onto the soil, believed to catalyse humus formation and encourage plant growth Question-define precision viticulture - Answer-makes use of data collected from the vineyard (soil, vigour, topography, plant growth) to respond to changes from plot to plot and from row to row Question-what is variable-rate application technology? - Answer-Interventions in the vineyard are targeted based on data collected Question-what goes into soil preparation when establishing a vineyard? - Answer-- rock removal
- subsoiling
- root removal
- weed management
- manure/compost/fertilizers
- ploughing
- pH adjustment
- landscaping Question-what considerations should be made when selecting planting material for a new vineyard? (14) - Answer-- time of budding
- ripening duration & timing
- drought tolerance
- disease resistance
- winter hardiness
- vigour
- wine style
- Yield
- cost
- laws
- availability
- market demand
- clones
- rootstock (based on pests, water, pH, vigour) Question-what 4 things are soil health dependent on? - Answer-- structure
- organic matter amount
- organisms
- nutrients Question-why is weed removal advantageous? - Answer-- eliminate undesirable competition
- bare, moist soils are best at absorbing heat during the day - > lower frost risk
- weeds hamper passage of machinery and personnel Question-what are organic fertilizers? what are their benefits? what are their detriments? - Answer-- derived from fresh or composted plant or animal material, such as manure or slurry
- reduction in vigor, difficulty in mowing, not suitable for steep slopes Question-what are advantages of mulching? disadvantages? - Answer-- no chemicals, reduce water evaporation, source of nutrients and humus
- bulky, a lot is needed, can increase vigor Question-what can help mitigate evaporation? - Answer-mulch, humus Question-what is RDI? when is water deficit usually scheduled? what are potentially detrimental effects of RDI? - Answer-- Regulated deficit irrigation: a system of timing and regulating the amount of irrigation so that the vine is put under mild to moderate water stress for a specified time within the growing season
- between fruit set and veraison
- lower yields, smaller berries Question-how can water be managed in high rainfall areas? - Answer-- artificial drainage systems
- natural vegetation
- removal of plough pans, improving soil structure Question-define canopy management - Answer-organization of the shoots, leaves and fruit of the vine in order to maximize grape yield and quality Question-name techniques involved in canopy management - Answer-- site assessment to determine ideal planting material and orientation
- vine training
- winter pruning
- vine trellising
- plant vigor management
- summer pruning; shoot pruning, positioning, pinching, trimming, leaf removal, green harvesting
Question-what factors should be considered when determining the most appropriate training and trellising method? - Answer-- vine vigor
- topography
- need for mechanization Question-describe head training - Answer-- relatively little permanent wood consisting of the trunk, sometimes with a few short stubs growing from the top of the trunk
- can either be spur-pruned or replacement cane-pruned. Question-describe cordon training - Answer-- typically a trunk and one or more permanent horizontal arms of permanent wood cordons
- usually spur-pruned
- takes longer to establish than head training due to the amount of permanent wood Question-define spur pruning - Answer-short sections of one-year-old wood (the shoots from the last growing season that have lignified) that have been cut back to only two or three buds
- can either be distributed along a cordon (cordon training) or around the top of the trunk (head training)
- easier to carry out than replacement cane pruning and can often be mechanized Question-define replacement cane pruning - Answer-- longer sections of one-year-old wood with anything between 8 and 20 buds, typically laid down horizontally and need tying to a trellis for support and positioning
- more complex than spur pruning and requires a skilled labor force to pick suitable canes and train them Question-what are the benefits and detriments of untrellised vines? - Answer-- simple & inexpensive, provides shade
- not possible to mechanize, canopy can become too dense
- Swellings on older roots
- Pale green leaf galls on the under-surface of the leaves
- Slow, stunted shoot growth and leaf yellowing appears in around 3 years, the plant dies after around 5 years Question-what are the two most commonly occurring nematodes? - Answer-root-knot and dagger Question-how can grape moths be managed? - Answer-- the bacterium Bacillus thuringiensis (which produces substances that are toxic to the moths)
- use of pheromone capsules to disrupt mating ('sexual confusion')
- natural predators (parasitic wasps, green lacewings, some spider species)
- insecticides Question-how can spider mites be managed? - Answer-- Make the environment inhospitable by the use of water sprinklers and/or cover crops or mulches to reduce dust
- Encourage predatory mites (by planting host species) that feed on spider mites
- General pesticides may kill beneficial predatory mites. Specific sprays can be applied to kill only the mites that are problematic in the vineyard, but this can add to costs. Question-what is the scientific name of powdery mildew? - Answer-Erysiphe necator aka Oidium tuckeri Question-when was powdery mildew introduced to Europe? - Answer-mid-1800's Question-which common varieties are particularly prone to powdery mildew? which are not? - Answer-- Chardonnay, Cabernet
- Pinot, Riesling Question-where is powdery mildew during the winter? - Answer-in buds, on canes
Question-what does powdery mildew attack? - Answer-young green parts of vines Question-what does powdery mildew look like? - Answer-- starts as dull grey patches that become black patches as they advance
- patches can damage young shoots, inflorescences and grapes, reducing yield
- grapes can split at véraison and become targets for other infections Question-what determines the growth rate of powdery mildew? - Answer-Temperature, optimal around 25C Question-what conditions are favorable to powdery mildew? - Answer-- optimal temperature (25C)
- shade
- can thrive in dry conditions Question-what causes downy mildew (peronospora)? - Answer-a water mold that lives within vine tissue, not on the surface Question-where did downy mildew originate? when was it introduced to Europe? - Answer-- North America
- late 1800's Question-what is the main effect of downy mildew? - Answer-attacks green parts of the vines, defoliates Question-what conditions are optimal for downy mildew? what are its symptoms? - Answer-- rainfall
- temperature = 20C
- yellow, circular 'oil spots' and then white, downy fungal growth on the underside of leaves
