PRUNING & TRAINING SYSTEMS Flashcards
What is the difference in amount of buds between cane and spur pruning?
Cane: 4 or more per cane
Spur: max 4 per spur
What could be a reason not to choose spur pruning?
Because the closest buds are less fruitful than the buds at the end.
What could be a reason not to choose spur pruning?
Because the closest buds are less fruitful than the buds at the end.
What is an optimal time to prune?
In the fall or winter when temperatures and infection rates are lower
In which weather conditions is it strongly advised not to prune?
During rain
Name one disadvantage of ‘old school’ pruning
(Assumed) less sap flow in the trunk of the vine due to necrosis from pruning wound
What is the risk of having ‘arms’ that are too long?
- Crossing canes will cause a ‘window’ in the canopy. And increased foliar density at the place where they cross, increasing risk of microclimate that can inhibit diseases like botrytis
Why is it a good idea to leave two extra buds on vines in area’s with increased frost risk?
In spring the vines will push the ‘extra’ buds at the end of the cane first. When spring frost hits it will only affect the buds that have already pushed. Hopefully the rest of the buds will not have pushed yet and stay out of harm.
What is a disadvantage of ‘new school’ pruning?
This type of pruning will cause more buds in spring, and so more work during bud rubbing period. Since winter pruning can be spread out over 3 months and the spring vineyard work have to be done in 3 weeks you could decide that that is too much extra work.
What is the result of late pruning? Do you have to take extra measurements in spring?
Late pruning means late ripening, means increased risk of bad weather during harvest time (later). So you need to do some leaf pulling early in the spring in order to speed up the ripening
What diameter cut will be regarded as a big cut?
2+ cm
What is the chemical equation for photosynthesis?
CO2 + H2O + energy –> C6H12O6 + O2
What is the function of photosynthesis? (3)
Plant growth
Grape maturation
Storage starch (sugar)
What is the optimal temperature for photosynthesis? At which temp does it slow down or stop?
Ideal: 25-30C
Slowing down from 35+C
Stopped: 40-42C
Why is leaf positioning important?
Because of optimising photosynthesis. A second layer of leaves only functions at 60-65%
What is meant with the ‘sink’ effect?
It means that the energy goes to ‘sinks’/’outlets’ of the plant and thus needs to increase it’s production. Photosynthesis is significantly higher when there are bunches (sink/outlet) present.
Which training system is more efficient for light interception and thus promoting photosynthesis? VSP or Gobelet?
Gobelet, all leaves are in the first light reception layer
What is the goal of a training system? (4)
Control vigor
Improve leaf/fruit microclimate
Optimize leaf area
Increase grape quality
What is the relation of vine density, leaf area and photosynthesis?
The higher the density the more leaf area and maximises the photosynthesis
What kind of spray can be used as ‘sunscreen’ for leaves and grapes?
Kaolinite
How much leaves does a shoot need in order to produce sugar?
8
From which slope % onwards do you need terraces or up-down rows?
10% slope
Name 4 things to do or not to do when erosion is a high risk in your vineyard
Use herbicide, not tilling
Avoid ripping
Mulch row line
Mow the inter-row
Why can an excess of vigour problem not be solved with close planting?
A high visor vine needs more space or a decided canopy or wide spacing. Otherwise it wil just make the canopy more dense and at risk for diseases due to microclimate in the canopy
How do you prune if a young vine that does not reach the wire in the first year?
Cut back to two buds
Where are vineguards/grotubes used for?
To encourage growth for newly planted vines.
What is ‘lignification’?
Cane ripening resulting in hardening of the wood, causes woodiness (brown parts instead of green)
Why do we prune a vine?
Because a vine is a liana. If not pruned it stretches out and becomes exhausted. It will produce a lot of wood and the vine will die rapidly after a few years
At what time does winter pruning take place?
A few weeks after harvest till mid-april (before the leaves merge)
What happens if you do the winter pruning late? Name 1 good and one risk
Good: you delay bud burst and thus risk of springfrost
Risk: you delay the ripening moment and thus risk of bad weather during harvesttime
Name one good thing and one risk for late winterpruning
Good: delay bud burst and thus risk of springfrost
Risk: delay ripening. Bad weather during harvest time can become a problem
When winter pruning. Which varieties do you prune first, the late or early ripening ones?
The late varieties because you will gain a few days on the vegetative cycle
In terms of biomass. When (g/vine) has a vine low or high vigor
Low <250 g/vine
High >450 g/vine
The technique layering increases risk of phylloxera, why?
Because there is no rootstock to protect the scion
