Transcript Water Berries

Water berry, Short berry, Pink berry
and Mummification of Grapes
Introduction
Grapes are cultivated in many countries of the world.
India produces only about 2.77 per cent of the total
world production. However, in productivity India
stands first with 23.5 t/ha.
As grape is cultivated in tropical regions against its
natural habitat, the vine physiology undergoes change.
When environmental factors exceed their optimal
conditions, grapevine undergoes stress and exhibits
certain disorders.
Grape disorders can be grouped into ecological,
physiological, eco-physiological and disorders of
unknown etiology.
Important grape disorders are
 Physiological: It is caused
by disturbances in normal
metabolic functions of the
vine by an unknown or
complex factors
Water berry
Shot berry
Mummification
 Eco-physiological: Due to
physiological disturbances
under the influence of
unfavourable environment
Pink berry
Water Berries
• The condition of berries wherein they lack normal
sugar, colour, flavour and keeping quality is referred as
water berries.
• It is associated with fruit ripening and most often
begins to develop shortly after berry softening
(Veraison).
• The affected berries become watery, soft, and flabby
when ripe (almost normal in size but their flesh is not
firm) and shrivel and dry by the time of harvest.
• Such berries mostly confine to the tip of the main rachis
or its branches.
• Reasons for this disorder: It occurs
due to high nitrogen status vine,
canopy shading, and cool weather
during fruit veraison and ripening.
How to manage?.
• Excessive
irrigation
and
nitrogenous fertilizers should be
avoided
during
berry
development to reduce the waterberry formation.
• Potash application during berry
growth period.
• Trimming off affected berries
during harvest is a common
practice,
although
labour
intensive.
Coutesy: Dr. Jagdev
Sharma, NRC-Grapes
2. Mummification
Though the etiology of
mummification in grapes is
not known (due to complex
factors), the affected water
berries in severe cases,
shrivel and dry at the time
of
harvest
leads
to
mummification.
Coutesy: Dr. D. S.Yadav
NRC-Grapes
Mummified berries on a cluster
(Photo: T. Zabadal)
3. Shot Berries
 Shot berries are smaller, sweeter, round and
seedless as compared to normal berries in a
cluster.
 Boron deficiency is the main cause of this
disorder.
 Affected leaves show spotty yellowing and
tend to be undersized and cupped.
 Affected clusters may totally abort or
develop a few small berries, often with many
small, green “shot” berries.
 Occurs either due to poor pollination and
fertilization or due to inadequate flow of
carbohydrates into the set berries.
A yellowing
cupped leaf
and an affected
cluster with
green short
berries (Photo:
T. Zabadal)
Reasons for the disorder:
• Boron deficiency, incorrect stages
of GA application and girdling
are the known reasons for
Coutesy: Dr. D. S.Yadav
shot-berry formation.
NRC-Grapes
• In the event of boron or Zinc deficiencies, ovary
fertilization is impaired due to restricted growth of
pollen tube.
How to manage?.
• Boron or Zinc deficiencies should be corrected.
• Prebloom application of GA (Gibrellic acid) at proper
stage should be ensured.
4.Pink Berry
In recent years, pink berry disorder is a wide spread
problem seen in all most all grape growing regions
of the country, whose cause is unknown.
This is a serious problem of Thompson Seedless in
Maharashtra.
As the bunch approaches maturity some berries
becomes pink colour at random.
The pink colour changes to dull red colour rendering
the bunch unattractive.
These berries become watery and collapse within a
few days after harvest and can not stand storage
and transport.
Reasons: This disorder is seen after
• Vines suffered prolong moisture
stress after veraison.
• Spray of calcium given after
berry softening.
How to manage?
• Avoid soil moisture stress
from berry softening.
Coutesy: Dr. D. S.Yadav
• Give adequate dose of potash. NRC-Grapes
• Avoid indiscriminate use of Etherel.
Let’s sum up
As grape is cultivated in tropical regions against its
natural habitat, the vine physiology undergoes
change.
When environmental factors exceed their optimal
conditions, grapevine undergoes stress and exhibits
certain disorders.
Water berry, Shot berry and mummification in grapes
are caused by disturbances in normal metabolic
functions by unknown or complex factors, whereas
pink berry occurs under unfavourable environment.
Proper care must be taken to avoid damage to grape
vineyards caused by various physiological disorders.