Agriculture Reference
In-Depth Information
harvested, the new planting can be started with corms or plants in bags
planted into the space between the double or single rows; once harvest has
fi nished the old plant stumps are eliminated. The big advantage of this, aside
from higher yields, is that harvest time can be decided in advance, to avoid
harvesting and marketing fruit when market prices are depressed because of
oversupply. Additionally, since plants become more susceptible to Sigatoka
after fl owering, a high-density planting system limits disease incidence in the
fi rst part of the cycle and reduces the need to spray for disease control. The
system is more appropriate for plantains, which normally do not last as long
planted in the fi eld as export bananas, and are normally replanted after two or
three harvest cycles. If a fi xed harvest season is important, the new planting
can be done in a dif erent fi eld if the original fi eld is not ready for replanting.
The system has also been successfully implemented for dessert bananas.
Cableway
Cableways are an important innovation in banana harvesting and handling
by the large banana exporters. The cableway greatly reduces mechanical
injury to the fruit during transportation to the packing house. It is also used to
take fertilizers and other materials to the fi elds. When 'Gros Michel', a tough-
skinned variety, was replaced because of Panama disease by 'Valery' and later
'Grand Nain', as both clones have delicate skins, it gave the impetus to use
cableways, as well as the use of packing boxes for export fruit.
Irrigation practices
Irrigation water can be supplied by furrow or over-canopy sprinkler, with
drip irrigation and micro-sprinklers becoming more popular. Irrigation is
used to supplement rainfall and its scheduling requires a calculation of
amount and frequency. This schedule is based on pan evaporation, soil water-
holding capacity, banana root depth, water depletion and crop water use.
The important characteristics of banana are its: (i) high water-loss potential,
associated with its large, broad leaves; (ii) shallow root system -
c.
90% of
roots are in the top 300 mm; (iii) poor ability to absorb water from a drying
soil; and (iv) rapid physiological response to water defi cit. Soil water potentials
more negative than −20 to −40
kPa can adversely af ect growth, with relative
impact depending upon local climate - hot and dry (severe impact) to moist
and humid (less impact). In the case of plantains, the same is true; however,
plantains are slightly more tolerant of water scarcity than dessert bananas,
but yield can be depressed by drought.
Micro-sprinkler use has become popular with banana and plantain
exporters in Latin America. Sprinklers are spaced ~11 m from each other,
