Page 55 - FRUTAS DEL TRÓPICO

pRuning stRategies to maximize tRopical mango yields fRom the
time of planting to RestoRation of old oRchaRds 55

stimulate a synchronized September vegetative flush in preparation for synchronized flowe-
ring at the anticipated normal flowering time in January-February. Experience has shown that

if a second vegetative flush does not occur in November or December after the September

flush in response to the tip prune, this tree will flower and produce a crop.

The height of the first pruning point, which ultimately determines the height of the lowest

branches, is determined by grower preference; however, it should not be lower than the se-

cond intercalation above the graft union. Trees will usually be ready to begin commercial pro-

duction after the fourth pruning due to the reduction in flushing frequency that would otherwise

continue unchecked in non-pruned trees. The final prune in the northern hemisphere tropics

should be done in August or early September for the resulting stems to achieve sufficient matu-
rity by the time of natural flowering in January-February. A similar strategy has been suggested

for dooryard mango trees grown in the subtropics (Campbell and Campbell, 2005).

Tip pruning to stimulate a synchronizing flush of vegetative growth

Tip pruning mature trees quickly results in one flush of lateral shoot growth if water is ade-
quate and leaf nitrogen levels are in a range of 1.1 to 1.4% (Davenport, 2003). This response

is critical to the success of a flowering management program. If the lateral stems produced

by this prune event remain in rest for four to five months, then flowering will usually occur

when initiated to grow either by cool temperatures or by foliar application of ethephon or a

nitrate salt, such as potassium, calcium, or ammonium nitrate in warm temperatures (>20 ºC,

night) (Davenport, 2000; Davenport, 2003; Davenport and Nuñez-Elisea, 1990; Davenport

and Nuñez-Elisea, 1997; Núñez-Elisea and Caldeira, 1988). Leaf nitrogen levels greater than
1.4% encourage a second flush of vegetative growth soon after that following the prune if

adequate water is available. This second vegetative growth flush eliminates the possibility of

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