Tamarind monograph.pdf - Crops for the Future

outcrossing. Heterogamous floral adaptation, protogyny and selfincompatibility
observed in tamarind may promote outcrossing under natural
conditions.
Fruit set in tamarind is influenced by environmental factors, age and size of
shoots, carbon : nitrogen ratio and the hormonal balance under which the
trees are grown, hence, high seasonal and annual yield variations can be
expected. Feungchan et al. (1996 c) attempted to increase fruit set of sweet
tamarind by the application of growth regulators at the time of flowering
(see also Chapter 6.2 where growth regulators and nutrient spray was noted
to affect flowering and subsequent fruit set). 4-CPA at 15 ppm , NAA at
100 ppm or GA 3 at 15 ppm were effective in increasing tamarind fruit set.
The growth regulator 4-CPA at 15 ppm was the most effective (Table 6.4).
The inducement of fruit set and fruit numbers per tree in sweet tamarind by
spraying growth regulators will be an important cultural practice, as is the
case of pineapple for year round fruit production. Further studies will be
required to establish the type of growth regulator, and its rate and time of
application for regular and enhanced pod yields.
6.6 Fruit development
Fruit development in tamarind has three distinct stages: growth, maturation
and ripening. The indehiscent pods ripen about 8-10 months after flowering
and may remain on the tree until the next flowering period (Benthall, 1933;
Chaturvedi, 1985; Rama Rao, 1975). In Mexico the fruits begin to dehydrate
203 days after fruit set and continue until 245 days when full ripeness occurs
and up to half the fruit’s original water content is lost. The fully ripened
fruits can remain on the tree for six months. Fruits are harvested at two
stages depending upon the market. Green pods are harvested for flavouring
and ripe pods for processing. The fruits of sweet types are also harvested at
two stages, half ripe and fully ripe. At the half ripe stage the pulp is
yellowish green and has the consistency of an apple, particularly in the case
of sweet forms. At the fully ripe stage the pulp shrinks, due to loss of
moisture, and changes to reddish brown and becomes sticky.
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