Here is a detailed power point presentation on physiological disorders in grapes.

1. PHYSIOLOGICAL
DISORDERS IN
GRAPES AND
THEIR REMEDIES
BY:
ROHITHA R

2. PINK BERRY FORMATION:
Disorder is common in Thompson Seedless and
its clone Tas-A-Ganesh [Maharashtra].
Pink blush develops on a few ripe berries close
to harvesting.
The pink colour turns into dull red and the
berry becomes soft and watery.
REMEDY: Spray 0.2% ascorbic acid and 0.25%
sodium dimethyl dithiocarbamate at fortnightly
intervals.

3. Pink berry formation:

4. SHOT BERRY:
The berries become under developed and
undesirable in the bunch.
Perlette is prone to this disorder.
This is due to the formation of number of
bunches on the wine.
REMEDY: Dipping the bunches at the berry
stage in ethephon @ 25 ppm for 1 minute will
control this disorder.

5. Shot berries:

6. Uneven ripening:
Presence of green berries in ripen bunch of
coloured grapes is called Uneven Ripening.
It is a varietal character and problem in
Bangalore Blue, Beauty Seedless and Gulabi Grapes.
Generally inadequate leaf area and non-
availability of reserves to a developing bunch is the
reason.
REMEDY: Application of Ethephon @250ppm at
colour break stage is recommended to reduce this
problem.

7. Uneven ripening:

8. Post- harvest berry drop:
This is due to weak pedicel attachment to
berries.
This disorder is common in Anab-e-Shahi,
Cheema Sahebi and Beauty Seedless.
REMEDY: Spraying of NAA @ 50 ppm, a week
prior to harvesting can minimize the post-
harvest berry drop.

9. FLOWER- BUD AND FLOWER DROP:
When panicles are fully expanded, the flower-
buds drop before the fruit set.
This is common in North India but not in
South India.
The reasons for this disorder is not known.
REMEDY: Stem girdling about 10 days prior to
full bloom can reduce this problem.

10. Flower-bud and flower drop:

11. Micronutrient deficiencies:
MAGNESIUM:
 The typical leaf chlorosis is easily recognized at
harvest time in heavy bearing vineyards, the leaves
towards the ends of the canes being most affected.
MANAGEMENT:
Foliar sprays of MgSO4 @ 1kg/100 liters of water.
ZINC:
The lower portions of the newly planted vine just
being trained up exhibit very small incupped leaves
called little leaves.
MANAGEMENT:
Foliar spray of ZnSO4@ 500g/ 100 liters of water
twice at 15 days interval before flowering.

12. BORON:
Boron deficiency in grapevine commonly reduces
fruit set.
Further productions of more number of small and
seedless fruits are seen surrounding the big berry.
This phenomenon of bunches with varying sizes is
called Hen and Chicken.
Such fruits will be sour in taste and naturally
weigh less than the fruits from normal vines.
MANAGEMENT:
The soil should contain 1 to 2 ppm of water-soluble
boron.
About 30 g of commercial borax per pit to rectify
this deficiency.
Foliar spraying of Borax @0.25% (2.5g/lit of water)
is also recommended.

13. Magnesium: zinc:
Boron: