Developmental Pysiology Part 2

Question 1

When is the final berry size decided?

Answer 1

Final berry size is decided between 1 - 3/4 weeks after flowering


Question 2

What are shot berries?

Answer 2

ovaries failing to develop properly

Question 3

Unfavorable conditions can also cause _____ in extreme cases

Answer 3

Early bunch stem necrosis

Question 4

Discuss the timing of determination of the following yield component: Number of vines/ha

Answer 4

At planting

Question 5

Discuss the timing of determination of the following yield component: Number of meters of canopy

Answer 5

At planting and training

Question 6

Discuss the timing of determination of the following yield component: Number of clusters/shoot

Answer 6

Bud differentiation (previous season)

Question 7

Discuss the timing of determination of the following yield component: Number of nodes per vine

Answer 7

Winter pruning prior to vegetative growth

Question 8

Discuss the timing of determination of the following yield component: Number of flowers per cluster

Answer 8

Prior and during bud break the year before

Question 9

Discuss the timing of determination of the following yield component: Number of shoots/node and what is the target?

Answer 9

At budbreak (current season) the year before. Target is 10 shoots/10 nodes

Question 10

Discuss the timing of determination of the following yield component: Number of berries/cluster

Answer 10

At fruit-set (current season)

Question 11

Discuss the timing of determination of the following yield component: Berry weight

Answer 11

From fruit-set to ripening (current season)

Question 12

There are many more cycles of cell division

Answer 12

before than after bloom

Question 13

Seedless grapes need exogenous _________ to increase berry size.

Answer 13

gibberellins or girdling

Question 14

__________ is generally more sensitive to T than is ________

Answer 14

1. Cell enlargement
2. Cell division

Question 15

_________ regulates cell division and _________regulate cell enlargement

Answer 15

1. cytokinins
2. gibberellins

Question 16

The Inflorescence and cluster respiration graph shows that

Answer 16

There is a large increase around veraison

Question 17

When do grape berries mainly grow?

Answer 17

At night

Question 18

Rather than setting a specific, inflexible target yield we should aim for….

Answer 18

The highest possible yield without sacrificing quality

Question 19

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?

Answer 19

1. Excessive is around 0.7 m2/kg
2. Optimal is around 1.65 m2/kg
3. Too low is around 3 m2/kg

Question 20

When does veraison really occur and what is the misconception?

Answer 20

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

Question 21

Before veraison there is a switch from….

Answer 21

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

Question 22

________ 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.

Answer 22

1. Xylem sap
2. Phloem sap

Question 23

_________represents the bulk of water loss from the berry. However the grape berries are 10-15 times lower than those of leaves for transpiration.

Answer 23

Berry transpiration

Question 24

_________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

Answer 24

Xylem back flow

Question 25

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 ____________

Answer 25

1. declines
2. much less pronounced.

Question 26

stiffening of the cuticle and decrease in skin extensibility causes

Answer 26

Cracking

Question 27

Permeability through the skin also increases with ______ and _______

Answer 27

1. Temperature
2. relative Humidity

Question 28

On the cluster where does flowering start and where does it finish

Answer 28

It starts in the middle and finishes on the top and bottom