Summary. Mango (Mangifera indica
cv. Kensington Pride) is the main horticultural tree crop grown in the
tropical regions of northern Australia. A major problem for growers is that
flowering and fruiting of this cultivar is highly variable from year to year.
A series of field experiments was conducted to evaluate cincturing and
chemical treatments as a means of improving mango productivity. A standard
cincture (Cincture) was compared with a modified technique in which twine was
tied tightly into a cincture groove (Twine). The chemical treatment was based
on a morphactin formulation (MF) and was introduced to the trees by either
painting directly onto the bark of the tree trunk (MF-paint) or soaking twine
in MF before tying it into a trunk cincture (MF-twine). The amount of
morphactin applied varied with tree age and was in the range from 0–0.06
g active ingredient (a.i.) per tree. Tree responses, measured in terms of
vegetative growth, flowering and fruiting, were compared with trees that had
been treated with a physical cincture only, or with paclobutrazol (up to 5.0 g
a.i.), applied as a collar drench.
In young (3–8-year-old) trees, Twine, MF-twine and MF-paint had a
positive effect on flowering and fruiting. These trees had earlier, more
intense flowering, produced early (September) maturing fruit (up to about
4-fold increase) and had high fruit production (up to about 2-fold increase in
fruit number) compared with controls. In some cases vegetative growth was
reduced by 50–60% compared with untreated trees. Twine and
MF-twine are favoured over MF-paint because (i) the paint must be applied
annually, incurring high labour costs, and (ii) paint treatments carry the
risk of overdosing the trees with morphactin. The positive effects of Twine
and MF-twine treatments were sustained, with large responses in flowering
and/or fruiting 2–4 years after application. The responses in fruit
production from paclobutrazol, applied at rates based on manufacturer’s
recommendations, were less than with Twine, MF-twine or MF-paint.
Tree Age Affects Postharvest Attributes and Mineral Content in Amrapali Mango (Mangifera indica) Fruits
