Agriculture Reference
In-Depth Information
an injection of herbicide into the pseudostems, resulting in the nematode
population being signifi cantly reduced; use of water isolation ditches so no
nematodes enter the fi eld through water coming from neighbouring fi elds;
use of healthy plant material - initially it could be tissue-cultured although
it is very expensive; use of tolerant or, hopefully in the near future, resistant
varieties and the reintroduction of biodiversity with new and dif erent green
manure or cover crops, manure incorporation and other practices (Rísede
et
al.
, 2010).
Weed management
Weeds are a major problem during stand establishment before canopy closure
occurs. Cultivation needs to be carefully carried out so as not to damage the
surface feeder roots, using hand-hoeing around the plants. Herbicides can
be used once the banana canopy is sui ciently high to avoid contact with the
leaves. Mulching and intercropping during early stand development can be
used. Failure to weed can lead to severe yield decline. It is very important to
keep the area around the new plants clean during the initial weeks until they
develop and then continue to clean until the shade of the canopies will reduce
the weed problem.
Orchard protection - windbreaks
Banana plants tolerate wind up to 30 m/s. Higher speeds lead to tearing of leaf
laminas. Windbreaks may be necessary if prevailing winds tear leaves into
strips less than 5 cm wide (Turner, 1994). The need for a windbreak must be
balanced against the ef ects of shading, the area needed, competition for water
and nutrients, and the limited protection on the leeward side. Plant propping is
carried out to reduce the impact of winds or the excessive weight of the bunch.
HARVESTING AND POSTHARVEST HANDLING
Harvesting
Individual fi ngers increase in weight and begin to lose angularity in cross
section during maturation. Fruits for export are harvested while still green
at 75% maturity with some angularity, 10-14 weeks after fl ower emergence
in the tropics and up to 9 months in the cool subtropical areas. The idea is to
export only fruit that is not over-aged and that has a minimum caliper. The age
of the fruit is established by tying a coloured ribbon to the bunch cover at the
time the cover is put in place, so the dif erent ribbon colours indicate the week
