Agriculture Reference
In-Depth Information
•
the marked changes that occurred in many areas in the varieties being grown
and the big increase in varietal diversity;
•
the importance of the CMD-resistant varieties which were first introduced in
the early 1990s and predominated in a third of all plantings by 2003;
•
the greatly increased traffic in cassava cuttings that occurred within and
between districts as a direct consequence of the epidemic;
•
the increased plantings of alternative staple food crops that were necessary until
cassava production was restored;
•
the big allocation of funds for cassava rehabilitation projects made by many
governmental and non-governmental organizations.
Only some of these changes and developments have been quantified and there is a
dearth of information from which to estimate the overall impact of the epidemic in
economic or social terms. Indeed, the official FAO statistics for Uganda give no
indication of decreased production as they show progressive increases since 1980 in
the area of cassava grown and in the production achieved. This is implausible and
indicates basic flaws in the method of data collection.
Indicative estimates of the losses caused by the CMD epidemic were made on the
assumption that each year in the mid-1990s an area of Uganda equivalent to four
whole districts was virtually out of production (Otim-Nape
et al.,
2000). This
represents an annual total of 60,000 ha, assuming an average of 15,000 ha per district.
Assuming productivity at 10 t ha
-1
, this is equivalent to an annual loss of 600,000 t,
worth US$6O million, at a conservative valuation of US$100 t
-1
. These are huge
losses, to which must be added the cost of developing control measures and of
mounting the various large-scale cassava rehabilitation projects. It is also necessary to
consider the diversion of national, donor and international resources that could
otherwise have been used to enhance cassava production, or to mount other
agricultural projects in Uganda or elsewhere.
The social and human costs of the epidemic are even more difficult to quantify
because some are largely intangible. Nevertheless, it is apparent that the epidemic
had a big impact on many communities, especially those relying heavily on cassava
as a subsistence crop and source of income to meet family requirements. National
and local government officials became gravely concerned at the social and economic
implications of the epidemic and were closely involved in the various cassava
rehabilitation projects, especially the distribution of CMD-resistant varieties.
Inevitably, cassava and CMD attained a high political 'profile' and it was calculated
that the disease had decreased overall national GDP.
The increased resources and attention that were given to cassava may eventually
be seen as a benefit arising from the epidemic in that it drew attention to the
importance of the crop and to the prospects for increased productivity by introducing
improved varieties and other innovations. Other very damaging epidemics have
ultimately been seen to have had such beneficial effects. For example, the severe
epidemic of
Helminthosporium
blight of maize in the USA in the 1970s drew
international attention to the dangers of genetic uniformity with several important
crops and of an undue dependence on a few genotypes of common origin (Ullstrup,
1972; Day, 1977). Previous tropical examples of such devastating diseases include
