CLIMATE CHANGE AND ITS POSSIBLE IMPACT ON THE EXISTENCE OF INSECT PESTSShimantini Borkataki, M. Devender Reddy, S.P. Nanda and Ritu Ranjan Taye
The impact of climate change is evident from increase in global average temperature, changes in the rainfall pattern and extreme climatic events. Global warming resulting in climate change represents a substantial challenge on a broad range of organisms with diverse life-history, traits and geographical distributions. The abiotic parameters are known to have both direct and indirect impact on insect population dynamics through modulation of developmental rates, survival, fecundity, dispersal and change in the physiological activities of the host. Among the abiotic parameters, temperature is considered as the most important factor. Both positive and negative effect of climate change on pest and their natural enemies could be seen. The alteration in the voltinism may also be the results of warming and it is more profit to multivoltine species and voltinism could be reflected in changes in the geographical distribution. Also some pioneering studies showed that increased temperature may also influence the insect immunity. Beside these, elevated CO2 also showed some impact on pestâs population abundance, the crop grown under the elevated CO2 could alter the nutritional value of host; it may alter the insect abundance and increase the consumption rate of herbivores. Therefore climate change would result in changes in the population dynamics of insect pests. Thus irreversible change in climate and gradual raise in temperature plays a pivotal role in insect population dynamics.