Developmental Pysiology Part 2 Flashcards
When is the final berry size decided?
Final berry size is decided between 1 - 3/4 weeks after flowering
What are shot berries?
ovaries failing to develop properly
Unfavorable conditions can also cause _____ in extreme cases
Early bunch stem necrosis
Discuss the timing of determination of the following yield component: Number of vines/ha
At planting
Discuss the timing of determination of the following yield component: Number of meters of canopy
At planting and training
Discuss the timing of determination of the following yield component: Number of clusters/shoot
Bud differentiation (previous season)
Discuss the timing of determination of the following yield component: Number of nodes per vine
Winter pruning prior to vegetative growth
Discuss the timing of determination of the following yield component: Number of flowers per cluster
Prior and during bud break the year before
Discuss the timing of determination of the following yield component: Number of shoots/node and what is the target?
At budbreak (current season) the year before. Target is 10 shoots/10 nodes
Discuss the timing of determination of the following yield component: Number of berries/cluster
At fruit-set (current season)
Discuss the timing of determination of the following yield component: Berry weight
From fruit-set to ripening (current season)
There are many more cycles of cell division
before than after bloom
Seedless grapes need exogenous _________ to increase berry size.
gibberellins or girdling
__________ is generally more sensitive to T than is ________
- Cell enlargement
- Cell division
_________ regulates cell division and _________regulate cell enlargement
- cytokinins
- gibberellins
The Inflorescence and cluster respiration graph shows that
There is a large increase around veraison
When do grape berries mainly grow?
At night
Rather than setting a specific, inflexible target yield we should aim for….
The highest possible yield without sacrificing quality
When looking at the graph showing Total leaf area–to-crop weight ratio and quality we can see that at certain points we have excessive crop, optimal, and too low of crop what are these points?
- Excessive is around 0.7 m2/kg
- Optimal is around 1.65 m2/kg
- Too low is around 3 m2/kg
When does veraison really occur and what is the misconception?
Veraison actually occurs several days prior to the color change when the berries begin to soften. It does not begin when the berries change color
Before veraison there is a switch from….
symplastic to apoplastic phloem unloading. Symplastic is the connection between cells. Apoplast is what surrounds the cells so apoplastic unloading is much easier as it can move around the cells instead of going through them
________ is the main source of water for the berry before veraison, accounting for about 75% of total water influx. After veraison, _________ becomes the primary or only source of berry water.
- Xylem sap
- Phloem sap
_________represents the bulk of water loss from the berry. However the grape berries are 10-15 times lower than those of leaves for transpiration.
Berry transpiration
_________when the plant takes water from the berries (water tank) to provide for the plant in extreme heat or just height of the day, this can lead to a slight shrinkage of the berry size
Xylem back flow
The sensitivity of berry water status to soil and vine water status greatly ________ after veraison, and the daily cycle of berry shrinkage during the day and expansion at night becomes ____________
- declines
- much less pronounced.
stiffening of the cuticle and decrease in skin extensibility causes
Cracking
Permeability through the skin also increases with ______ and _______
- Temperature
- relative Humidity
On the cluster where does flowering start and where does it finish
It starts in the middle and finishes on the top and bottom
