Validation of a Vigor Map the Ground Truthing

Question 1

Optimal vigor is the target, but what does that really mean

Answer 1

Optimal means a balance and it can depend on many different variables. Its not always the case the high, medium, or low vigor are always good or bad.

Question 2

With less pruning weight we have…

Answer 2

More vigor

Question 3

What are some issues associated with too high of vigor?

Answer 3

If the canopy is too dense due to high vigor, there can be a lack of air flow, competition, as well as issues with photosynthesis and berry ripening

Question 4

Vine Balance index

Answer 4

When the yield to pruning weight ratio is:
<5 we have an excess of vigor
5-8 we have a balance
>8 we have an excess of fruit

Question 5

Is it possible to map the vine balance

Answer 5

Yes and it is important to look at the relationship between “quality” of fruit and leaf to fruit ratio

Question 6

what are the 6 overarching categories of Materials and Methods

Answer 6

1. Growth
2. mineral nutrition
3. bunch health
4. Yield Components
5. Vine Balance
6. Must and Berry Composition

Question 7

Components for Growth, Mineral nutrition, and bunch health (6)

Answer 7

1. Nutrition status
2. Shoot length
3. Shoot fertility
4. Leaf Area (Main and Laterals)
5. Pruning weight
6. Bunch rot incidence and severity (at harvest)

Question 8

Components for Yield Components (3)

Answer 8

1. Bunch number and yield per vine (at harvest)
2. Berry weight, skin, flesh, and seed relative weight
3. Bunch Compactness (g/cm)

Question 9

Components for Vine Balance (2)

Answer 9

1. Ravaz Index (Yield/Pruning weight)
2. Leaf-to-fruit ratio

Question 10

Components for must and berry composition (3)

Answer 10

1. Ripening Sampling (weekly)
2. Must composition at harvest
3. Total soluble solids, titratable acidity, malic and tartaric acid, K+, total anthocyanins and phenols

Question 11

What was significant of the results when looking at growth and mineral nutrition?

Answer 11

We can see that pruning weight of laterals is linearly equated with vigor

Question 12

What is important for the Brolio vineyard chart

Answer 12

That with high vigor we had the highest yield per vine, but lowest levels of Brix, polyphenols, and anthocyanins

Question 13

Is there a linear correlation between yield and vigor?

Answer 13

No

Question 14

When looking at a graph displaying a relationship between Yield per Row Meter and Vegetation Index (NDVI) what is important to note about varying levels of high and low vigor

Answer 14

What is important to note is that different grape varieties in different locations have different thresholds and baselines for what low to medium to high vigor looks like

Question 15

With Botrytis and bunch health, what trend can be seen with high, medium, and low vigor and what are the three factors to be taken into consideration

Answer 15

With high vigor there was the highest incidence percentage and severity percentage.

1. Bunch Microclimate
2. Bunch compactness
3. Skin thickness

Question 16

Juice and fruit composition study reveals 4 important things

Answer 16

1. TSS is dependent on canopy efficiency
2. There are more shaded leaves in HV plants resulting in more K+ from low level leaves which is attracted by fruit. (K+ is also positively correlated to pH resulting in higher pH with HV)
3. In HV the bunch shading limits the degradation of malic acid
4. Lower amounts of total polyphenols and anthocyanins in HV