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Fruits
> Grape
> Harvesting
The proper stage for harvesting the grapes is
adjudged by the development of characteristic
colour of a variety and also by touching the grapes
from the apical portion of the bunch. In grapes
three major colours, viz. White, red and black
are found. The criteria used to judge ripening
differ according to the use of the grapes. For
making raisins, harvesting at a late stage is
preferred, to get more sugar in grapes for increasing
the weight of the dried product. For all other
purposes, ripening is judged on the basis of sugar:
acid ratio for getting proper blend required for
table purpose or wine making. The correct blend
of sugar acid ratio should be between 25-30.
For harvesting grapes for export market, the
following parameters are considered-Berry size-
should be more than 16mm in diameter.
- TSS- should be more than 17° Brix.
- Bunch weight- should be between 300-750 g.
- Bunch colour- milky green.
- The selected bunch should not be compact.
- All the berries should be of uniform colour
and size in a bunch.
- Less than 2% sunburnt or Sulphur bleached,
bruised or crushed berries.
- Pedicel should be fresh and green.
For local markets, the grapes are harvested early
in the morning by cutting selected bunches with
long nose scissors. Care must be exercised not
to injure other berries by the scissors. While
harvesting, care should be taken to avoid erasing
the waxy coating by holding the stem of the bunch
by hand. The harvested bunches are kept in perforated
plastic trays. Bunches should be trimmed by removing
the decayed or otherwise defective berries before
packing.
For export purpose, harvesting has to be done
in early hours of the day. It should be stopped
when the berry temperature raises above 20°
C. It is advisable to close harvest by 10 a.m.
otherwise the berry temperature can not be brought
down to 4° C within the stipulated time of
six hours by precooling. The selected bunches
are harvested by giving a cut above the knot present
on the stalk of the bunch. Any type mechanical
injury to berries should be avoided while harvesting
and handling. The injured portion of skin serves
as the entry point for many fungi causing decay.
Harvested bunches are places gently in clean perforated
plastic trays in not more than two layers and
shifted to the packing shed without losing time.
Yield
A well-maintained vineyard starts yielding from
3 years after planting under north Indian conditions
and even in less than 2 years under tropical conditions.
A well-maintained vineyard of Perlette gives a
yield of 25-30 t/ha in North India while Thompson
Seedless gives 15-20 t/ha.
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