Page 106 - Ecuador's Banana Sector under Climate Change

ecuador’s banana sector under climate change: an economic and biophysical assessment to promote a sustainable and climate-compatible strategy
increase in temperature during the rainy season will remain within the optimum range. Short heat waves of excessively high temperature appear unlikely.
As a result of higher temperatures throughout the year, bananas will have
an increased demand for water, reaching 12-15 percent increase over current conditions by 2070. This demand for water will be primarily in the dry season. No changes in the distribution of rainfall during the year are projected, with only slight increases in the amount of rainfall in certain rainy season months.
In summary, the average climate change projected for coastal Ecuador may require some adjustments in production practices. It does not, however, appear to present a major threat to sector productivity.
2.6.2 Biotic condition: pests and diseases
Month-to-month rainfall distribution is not projected to vary even through 2070, although temperatures are projected to increase. Since the dynamic of BS is not highly temperature-dependent but more linked to leaf wetness, little change is projected in the BS rate of evolution due to average climate change.
Increased temperatures, however, may result in an increase in the velocity
of the growth of the BS spore germination tube and a resulting increase in the aggressiveness of the disease. Since fungicide applications are timed primarily to protect new leaves, increased fungicide application frequency may result from the increased leaf emergence rate.
Pests, such as nematodes and stem weevils, will have accelerated growth with higher temperatures, which will lead to shorter cycles of reproduction and a greater potential for damage with more explosive populations. However, very little is known about the longevity response of adult weevils and nematodes. Shorter life cycles in response to higher temperatures could potentially serve to dampen pest response to increased temperatures. In addition, little information is available on the temperature response of the natural control agents of weevils and nematodes. Increased activity in response to climate change by Beauvaria bassiana or predatory nematodes could compensate the potentially more explosive weevil or plant-parasitic nematode populations.
In summary, while simple models suggest that pests and diseases will not have an outsized response to the project change in climatic averages, the interactions of the crop-pest/disease beneficial organisms need to be studied. These studies will require greater depth to predict with greater understanding their response.
2.6.3 Weather variability
Current variability in weather from one year to the next represents an important factor in the management of the banana. Certain types of extreme and moderate events are easier to address through management than others. The excess rains associated with El Niño of 1998 resulted in far more disruption than the unusually high temperatures during July and August in certain years, which actually may have increased banana productivity.
The potential for increasing frequency of moderate and extreme weather variability is a large unknown in projections. An increased frequency of years,
90