Methods for Assessing Efficiency of Different Training Systems Flashcards
What is upscaling and why is it a problem
When we measure the photosynthesis of every single leaf, the measurement is not representative of the whole canopy, we need to be sure that the measurement that we take in the single leaf can be upscaled and extrapolated at the whole canopy level.
Three considerations for upscaling?
- Leaf
- Shoot
- Canopy
3 classifications for trellis systems
- Single vs. divided canopies
- VSP vs. Free growing canopies
- Orientation of the canopy wall
4 aspects of canopy “efficiency”
- Amount of available light
- Amount of intercepted light
- Dry matter exported to clusters
- Amount of light converted into dry matter
How can we visibly check the amount of intercepted light
by looking at the amount of ground that is shaded by the canopy
The smaller the distance between rows…
the greater will be the radiation interception on a vineyard area basis.
light is decreasing from…
the top to the bottom of the canopy
What is happening here?
Here PFR is light intensity and leaf contact number corresponds to leaf layer number. On a sunny day the first leaf layer gets almost everything and leaves very little for the next leaf layers, on an overcast day there is a better distribution as the majority of light is diffused and not direct
What is the Ravaz Index
A vine balance index that shows Yield/pruning weight
Discuss this visual
The picture on the left shows for instance a condition of overvigorous vine, in the middle the vine is more balance, on the right a condition of overcropping.
What is a potential limit of this kind of index?
The difficulty with the measurement of pruning weight is that it can be inaccurate, instead we should use the leaf area to yield ratio
Any model has two main issues:
- The type of input (simple inputs, if they are too simple, accuracy wont be enough)
- If too complicated the model with be too complex
excessive canopy density can…
decrease overall quality
