Page 28 - FRUTAS DEL TRÓPICO

28 Frutas del trópico

trees. Once a flowering response is observed, then each section of the orchard, according to
the order and timing of pruning, can be sprayed.

Results correlating high leaf nitrogen levels with frequent vegetative flushes lychee (Men-

zel et al., 1988, 1992) are directly applicable to management of mango. It is advisable that

leaf analyses should be conducted on the last flush of leaves at least one or, preferably, two

times per year. If one analysis is conducted per year, it should be done just prior to the syn-

chronizing prune. The leaf nitrogen levels for mango should be 1.1 to 1.4% at the time of the

synchronizing prune event in order to avoid possible second flushes (T.L. Davenport, unpu-

blished observation). The second analysis should be conducted just prior to floral stimulation.

Sufficient nitrogen should be applied in the bulk fertilizer at the time of flowering to provide
the levels needed to maintain good fruit set and development without retaining any residual

nitrogen after harvest that may raise the leaf nitrogen levels for the next synchronizing prune.

It is essential that the trees receive all of the necessary macro and micronutrients for healthy

growth. Appropriate levels of P, K, Mg, S, and minor elements are necessary, as determined

by leaf analyses, while managing nitrogen in the low range in order to control the frequency

of vegetative flushes.

The type of irrigation used for mangoes is an important consideration if flowering mana-
gement is desired. Most growers in the tropics who have irrigation to furnish water to trees

through the typical six-month annual dry season use furrow irrigation along the tree rows

(personal observation). In-row furrow irrigation has the disadvantage of providing water pe-

riodically around the base of trees. The major problem is that many roots outside the limits

of the irrigation ditches never get watered during the dry season; hence, water moves from

roots located in or near the irrigation ditches to not only the canopy but also out to the dry

roots in response to water potential gradients in the root system (Boyer, 1985; Canny, 1995;

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