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Albrigo and Galán Saúco ( 2004 ) there is some evidence that, in the absence of
low temperatures, the initiation of floral differentiation will usually occur after a
long period of water stress. It is also clear that such a dry period can increase the
intensity and synchrony of flowering, both in tropical and subtropical climates,
although the response can vary with cultivar. In addition, the age of the wood
is important for mango flowering: the older the wood, the more readily it will
flower after any form of stress.
The mango is not a continuous growing tree, but has flushes of shoots develop-
ing from apical or lateral buds that occur at discontinuous, intermittent intervals
(Nakasone et al. 1955 ; Davenport 2009 et passim ). Flowering also stops the vegeta-
tive growth of mango terminals. The typical growth pattern of mango development
consists of vegetative flushes ending with the formation of determinate inflores-
cences. After fruiting and harvesting, the terminal growth usually produces one or
several growth flushes (intercalary units), depending mainly on temperature and
cultivar but will eventually reach a resting stage. The apical resting bud of each
intercalary unit is surrounded by a densely packed whorl of around 12 leaves with
short internodes and has several preformed nodes containing a leaf bract or leaf pri-
mordial and a lateral meristem contained within. Depending on the inductive condi-
tions, these apical buds may develop into vegetative or into reproductive shoots on
which the lateral meristems, such as the bracts and primordia, do not fully develop.
By contrast, the lateral meristem then starts to elongate and alters after several
transformations that give rise to the inflorescence. The behaviour of the terminal
meristems of the mango is more complex. In reality, six different shoot types, i.e.
totally vegetative, totally flowering, mixed panicle, 2 transition stages (vegetative-
to-flower and flower-to-vegetative) and chimeral (flowers on one side and leaves
on the other) may develop mainly depending on the duration of low temperature
at the time (Davenport 2009 ), with the interval between differentiation and flower
emergence being as short as 29 days (Goguey 1995 ). This condition may explain
why some flower shoots undergo a reversal from vegetative to floral shoot or vice
versa as well as changes the frequency of mixed shoots when temperature condi-
tions change sharply. However, according to Kulkarny ( 2004 ), the emergence of the
different types of shoots is a consequence of the interaction between the floral pro-
moter and the floral inhibitor that controls flowering in mangoes. As in many other
tree crops, flowering can be suppressed or considerably delayed by the application
of giberellic acid (GA 3 ). There are also indications that moderate applications of
GA 3 can increase the proportion of missed shoots (Vázquez-Valdivia et al. 2009 ).
As a consequence of its peculiar flowering behaviour, flowering can be ma-
nipulated out of season. If the terminal flowering is destroyed, either by climatic
or phytopathological reasons, the use of chemical sprays or pruning, or delaying
the flowering by GA 3 sprays, the relatively low environmental temperatures oc-
curring under subtropical conditions allow the emergence of a second flower-
ing mainly from buds located at the base of either the terminal node, or axillary
buds (Galán Saúco 2009 ). Stressed conditions provide for a second flowering,
unlike the first flowering produced before the end of the winter, and in response
to spring temperature which are high enough to ensure good fruit set. A similar
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