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The cotton aphid, Aphis gossypii, is a major sap sucking insect of cultivated cotton, Gossypium sp. We investigated the effects of temperature on the biological parameters of A. gossypii by fitting different non-linear models to the data obtained from constant temperature experiments carried out between 12 and 32 degrees C. The pest risk in different geographical areas was simulated using GIS tools and represented by two spatial indices viz. establishment risk index (ERI) and generation index (GI). The results revealed that the development rate as a function of temperature increased linearly until approximately 27 degrees C, after which it became non-linear. Mean longevity of adult female was highest at 12 degrees C (10.10 +/- 0.33 days) and shortest at 32 degrees C (3.70 +/- 0.14 days). The lower and upper development threshold temperatures predicted for immature development of A. gossypii were 6.24 degrees C and 34 degrees C, respectively. The temperatures between 22 and 27 degrees C were found as favourable range for A. gossypii development, survival and reproduction. Majority of the Indian cotton areas were predicted optimally suitable for establishment and survival of A. gossypii (ERI > 0.6 and GI > 30.0). The risk mapping based aphid management strategy is suggested in the conclusion section of this article.