Impacts on Insect and Mite Pests - Climate Resilient Agriculture for Ensuring Food Security - page 113

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Impacts on Insect and Mite Pests

Abstract
The occurrence of climate changes is evident from increase in global aver-
age temperature, changes in the rainfall pattern, and extreme climatic
events. Climate and weather can substantially infl uence the fauna, fl ora,
population dynamics development, and distribution of insects.
Anthropogenically induced climatic change arising from increasing levels
of atmospheric greenhouse gases would, therefore, be likely to have a sig-
nifi cant effect on agricultural insect pests. Current best estimates of changes
in climate indicate an increase in global mean annual temperatures of 1 °C
by 2025 and 3 °C by the end of the next century. Such increases in tempera-
ture have a number of implications for temperature-dependent insect pests
in midlatitude regions. Changes in climate may result in changes in geo-
graphical distribution, increased overwintering, changes in population
growth rates, increases in the number of generations, extension of the
development season, changes in crop-pest synchrony, changes in interspe-
cifi c interactions, and increased risk of invasion by migrant pests.
Impacts of climate change on crop production mediated through changes
in populations of serious insect pests need to be given careful attention for
planning and devising adaptation and mitigation strategies for future pest
management programs. Therefore, there is a need to have a concerted look
at the likely effects of climate change on insect pests and devise appropriate
measures to mitigate the effects of climate change on food security.

Keywords
Climate change • Insects • Mites • Population dynamics • Geographical
distribution • Winter survival • Impact models

Crop plants used as a food by human beings are
damaged by over 10,000 species of insects and
cause an estimated annual loss of 13.6 % globally
(Benedict 2003 ). Damage by insect pests is

usually caused by chewing on plant tissues or
sucking the plant sap (e.g., aphids). In many
cases, insect pests also transmit viruses, which
then affect the plant.