Page 25 - FRUTAS DEL TRÓPICO

25
RepRoductive physiology of mango

Synchronization of the vegetative growth of tree canopies in an orchard is a necessary
first step in the flowering management program. Synchronous growth throughout each tree

allows all of the stems in the canopy to be in the same physiological stage of maturity so that

management can be most efficiently achieved uniformly throughout a section of orchard. Syn-

chronized growth is best accomplished by tip pruning all of the stems on the trees (Tables 1

and 2). Tip pruning not only causes a uniform flush of growth throughout the canopy, it re-

moves growth—and flower—inhibiting factors in stems derived from the previous season’s

flowering and fruiting panicles (Davenport, 1990, 2000; Davenport and Nuñez-Elisea, 1997).

Tip pruning also stimulates lateral shoot development forming five to 10 times the original

number of productive stems. It is essential that trees have adequate water at the time of pru-
ning to facilitate a rapid flushing response because even mild water stress during the tropical

dry season discourages shoot initiation.

Deeper level pruning to shape trees, cutting branches as small as 2 cm, usually results in

a second vegetative flush occurring about three months after the first. It is essential that there

be only one flush of vegetative growth that occurs about one month following the synchro-

nizing prune. The depth of the pruning cut, management of fertilizer (through monitoring of

leaf nitrogen levels) during the wet season, and management of water during the dry season
are important factors governing the probability of a second, undesirable flush occurring before

the desired time of floral stimulation. All three factors interact to promote or discourage an

early second flush. Reducing the negative impact of one factor is usually sufficient to prevent

occurrence of the second flush when given ample presence of the other two. For example,

reducing water availability such that the plants are under mild water deficit cause trees to flush

only once following pruning regard less of depth of pruning or nitrogen levels. Similarly, reduc-

tion of leaf nitrogen levels discourages a second flush during rainy seasons.

Universidad Autónoma de Chiapas