Diseases and Management of Crops under Protected Cultivation

Introduction
(Diseases and Management of Crops under Protected Cultivation)
Climate Change and Plant Diseases
Suresh Pande
International Crops Research Institute for the Semi-Arid Tropics Patancheru-502 324 (AP)
The earth’s climate is a dynamic process and it has always responded to changes in the
cryosphere, hydrosphere, biosphere, and other interacting atmospheric galaxies. Although the
effects of climate change on plant diseases was assessed in early nineties for New Zealand
(Prestige and Pottinger 1990) and United Kingdom (Atkinson 1993). However, how the changing
climate may influence the plant pathogens and the diseases they cause gained international
importance only after Manning et al. (1995) first reviewed the impact of changing atmospheric
CO 2 , O 3 and UV-B on plant diseases. Soon after the presentation on “potential impact of climate
change on plant–pathogen interactions” in the 7 th International Congress of Plant Pathology in
1998 by Chakarborty et al. (2000), plant pathologists recognized that changes in climate will affect
plant diseases together with other components of global change
i.e. anthropogenic processes such as air, water, and soil pollution, long-distance introduction of
exotic species and urbanization (Gurr et al. 2011; Bradley et al. 2012; Matyssek et al.2012;
Regniere 2012).
Each year 10-16% of global harvest (Strange and Scott, 2005; Oerke 2006) is
lost to plant diseases costing US$ 220 billion, with the emerging climate change scenarios the
losses caused by plant disease are expected to be increasing by 3-4 folds.
To guide government policy and industry strategic decision–making, there is need to
assess impacts of climate change on disease induced losses in food crop yields (Gregory et al.
2009). In a world where more than one billion people currently do not have enough to eat (Anon
2009), more work is needed to understand the impact of climate change adaptation procedures
available to decrease predicted disease-induced losses in crop yields.In this article,though the
focus is on plant pathosystemsit also can be argued for invertebrate pests.
Need
The well-known interaction between host × pathogen ×environment for plant disease
epidemic development and weather based disease management strategies have been routinely
exploited by plant pathologists. However, the impact of inter annual climatic variation resulting in
the abundance of pathogen populations and realistic assessment of climatic change impacts on
host-pathogen interactions are still scarce and there are only handful of FACE and OTC studies.
Climate change predictions, point to a warmer world with in the next 50 years, a trend that
is increasingly being supported by ‘ground-truth’. Climate change threatens to increase crop
losses, increase in the number of people facing malnutrition, and changing the development
patterns of plant diseases. Agriculture production of rainfed regions, which constitute about 65% of
the area under cultivation and account for about 40-45% of the total production in India, varies a
great deal from year to year. Therefore in order to sustain and enhance the production of the
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