Impacts on Insect and Mite Pests - Climate Resilient Agriculture for Ensuring Food Security - page 123

Fig. 7.3 Impact of climate change on range expansion of insect pests

this insect as a pest in North America will increase
dramatically. Many insects such as Helicoverpa
spp. are migratory and, therefore, may be well
adapted to exploit new opportunities by moving
rapidly into new areas as a result of climate
change (Sharma et al. 2005 ).
Published reports of empirical studies on
impact of climate change on future geographic
range and distribution of insect pests are pre-
sented in Table 7.4 .
Projected trends for several pests are summa-
rized in Table 7.5 . Examples of the midpoint pro-
jections of WCR infestation areas in maize are
shown in Table 7.6 .
Projected trends to 2020 are expected to con-
tinue up to 2050 and beyond and are useful stra-
tegic indicators for the plant breeding and crop
protection industries.

pests on crops. Likewise, the timing of arrival of
insect species can also be recorded through light
traps, suction traps, or pheromone traps. Analysis
of long-term data on phenology would reveal
changes in the timings of pest appearance under
climate change.
Analysis of suction trap data at the Rothamsted
Insect Survey since 1964 has revealed that spring
fl ights of the peach potato aphid ( Myzus persi-
cae ) started two weeks earlier for every 1 °C rise
in combined mean temperature of January and
February.
Likewise, long-term data from several insect-
recording schemes in Europe and North America
have provided evidence for species becoming
active, migrating, or reproducing earlier in the
year due to increases in temperatures that lead
directly to increased growth rates or earlier emer-
gence from winter inactivity (Roy and Sparks
2000 ). Increasing temperatures have also allowed
a number of species to remain active for a longer
period during the year or to increase their annual
number of generations.
Under the All India Coordinated Rice
Improvement Project (AICRIP) of ICAR, there is
a widespread network of coordinating centers all
over India that collect light trap insect data round

7.6 Changes in Phenology

Recent climate change has led to an ecological
shift in time, with changes in species' phenology.
Changes in insect phenology can be studied
through long-term experiments with variable
sowing dates for observing the appearance of