Impacts on Plant Pathogens - Climate Resilient Agriculture for Ensuring Food Security - page 149

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Impacts on Plant Pathogens

Abstract
Changes in atmospheric composition and global climate continue in the
future as predicted, there will be relocation of crops and their diseases and
impacts will be felt in economic terms from crop loss. Changes in levels of
CO 2 , ozone, and UV-B will infl uence disease by modifying host physiol-
ogy and resistance. In addition, changes in temperature, precipitation, and
the frequency of extreme events will infl uence disease epidemiology.
Changes in geographical distribution will potentially alter the relative
importance and spectrum of diseases, and new disease complexes may
arise. Evolution of pathogen populations may accelerate from enhanced
UV-B radiation and/or increased fecundity in elevated CO 2 . As a result,
host resistances may be overcome more rapidly. Disease management will
be infl uenced due to altered effi cacy of biological and chemical control
options. Given the multitude of atmospheric and climatic factors, possible
change scenarios, and the number of disease systems, modeling approaches
to impact assessment need to be strengthened. Changes in both mean tem-
perature and its variability are equally important in predicting the potential
impact of climate change. Given that climate change is a global issue, the
focus needs to shift from paddock-based assessment on specifi c diseases
to a more ecologically relevant spatial unit to consider climate with other
associated changes in land use and vegetation cover, among others.

Keywords
Climate change • Impact on plant diseases • Geographical ranges •
Adaptation • Mitigation