WSET Diploma D1 - CH 2 - The Vine Growth Cycle | Questions with
Correct Answers and Answers with Verified Solutions | Latest 2026
Update
Q: Which grape varieties are most/least susceptible to spring frost damage?
Answer:
Late budding ones are least susceptible. How can pruning be used to affect
budbreak? Pruning late can delay budburst When is the fastest rate of growth of a
vine? Between budburst and flowering. What is most energy directed towards during
budburst? Shoot growth What nutrients are needed after budburst for shoot growth?
Nitrogen, Potassium, Phosphorous What other natural factors can affect shoot
growth? Can be impaired by dry soils and water stress. What can stunted shoot
growth lead to? Poor quality and loss of yields. What is bud fruitfulness? The level of
the number of inflorescences that develop from a bud. What can affect bud
fruitfulness? Limited by low temps, water stress, nutrient deficiency. Also, some
variation among varieties. Which variety is known to have fruitful buds even in cold
temps? Riesling
, Q: What would low bud fruitfulness affect?
Answer:
Could decrease yields What happens during pollination? Pollen laden stamen
exposed. Pollen lands on moist stigma. What happens during germination? A pollen
tube is produced which penetrates the stigma and then the ovule in the ovary and
delivers sperm cells to fertilize the eggs in the ovary. Where do seeds come from?
How many in a grape? Fertilize ovules. Up to 4. Where do pulp and skin come from?
Enlargement of the walls of the ovary. What is fruit set? Transition of flower to
grape. Are vines self pollinating? yes When does flowering happen in relation to
budbreak? Usually < 8 weeks How does temperature affect flowering? Warm
conditions are favorable where inflorescences can flower within a few days. Low
temps can lengthen the duration to weeks and have negative effects on evenness of
ripening. What percentage of flowers become fruit? About 30%
Q: 0-60% possible. Temps required for germination?
Answer:
79-90 F cold, rainy, windy conditions affect pollen tube growth and can affect yields.
hot dry windy conditions can lead to water stress and can reduce yields as well. What
is Coulure? Fruit set fails of high percentage of flowers due to unsuccessful
fertilization which can drastically reduce yields. What causes coulure? cold, cloudy
or hot, arid conditions leading to a low rate of photosynthesis. Also, from vigorous
shoot growth which diverts carbohydrates from inflorescence due to fertile soils,
vigorous rootstocks or heavy use of fertilizer. Which grapes are most susceptible to
Coulure? Grenache, Merlot, Malbec What is Millerendange? When cold, wet, windy
conditions at pollination/fruitset cause a high proportion of seeds not to form. This
causes small berries with green unripe flavors. Reduces volumes and reduces quality.
Grapes susceptible to Milelrendange? Chardonnay, Merlot What are the four phases
of grape development? Formation
Correct Answers and Answers with Verified Solutions | Latest 2026
Update
Q: Which grape varieties are most/least susceptible to spring frost damage?
Answer:
Late budding ones are least susceptible. How can pruning be used to affect
budbreak? Pruning late can delay budburst When is the fastest rate of growth of a
vine? Between budburst and flowering. What is most energy directed towards during
budburst? Shoot growth What nutrients are needed after budburst for shoot growth?
Nitrogen, Potassium, Phosphorous What other natural factors can affect shoot
growth? Can be impaired by dry soils and water stress. What can stunted shoot
growth lead to? Poor quality and loss of yields. What is bud fruitfulness? The level of
the number of inflorescences that develop from a bud. What can affect bud
fruitfulness? Limited by low temps, water stress, nutrient deficiency. Also, some
variation among varieties. Which variety is known to have fruitful buds even in cold
temps? Riesling
, Q: What would low bud fruitfulness affect?
Answer:
Could decrease yields What happens during pollination? Pollen laden stamen
exposed. Pollen lands on moist stigma. What happens during germination? A pollen
tube is produced which penetrates the stigma and then the ovule in the ovary and
delivers sperm cells to fertilize the eggs in the ovary. Where do seeds come from?
How many in a grape? Fertilize ovules. Up to 4. Where do pulp and skin come from?
Enlargement of the walls of the ovary. What is fruit set? Transition of flower to
grape. Are vines self pollinating? yes When does flowering happen in relation to
budbreak? Usually < 8 weeks How does temperature affect flowering? Warm
conditions are favorable where inflorescences can flower within a few days. Low
temps can lengthen the duration to weeks and have negative effects on evenness of
ripening. What percentage of flowers become fruit? About 30%
Q: 0-60% possible. Temps required for germination?
Answer:
79-90 F cold, rainy, windy conditions affect pollen tube growth and can affect yields.
hot dry windy conditions can lead to water stress and can reduce yields as well. What
is Coulure? Fruit set fails of high percentage of flowers due to unsuccessful
fertilization which can drastically reduce yields. What causes coulure? cold, cloudy
or hot, arid conditions leading to a low rate of photosynthesis. Also, from vigorous
shoot growth which diverts carbohydrates from inflorescence due to fertile soils,
vigorous rootstocks or heavy use of fertilizer. Which grapes are most susceptible to
Coulure? Grenache, Merlot, Malbec What is Millerendange? When cold, wet, windy
conditions at pollination/fruitset cause a high proportion of seeds not to form. This
causes small berries with green unripe flavors. Reduces volumes and reduces quality.
Grapes susceptible to Milelrendange? Chardonnay, Merlot What are the four phases
of grape development? Formation
