| Climate change has become the most significant environmental problem and thus caused great concern for public. Aphids, a worldwide agricultural pest, are considered as an important insect group indicator of global warming due to their short generation time and low developmental threshold temperature. Climate change - particularly global warming - will have significance on revealing the ecological mechanism of wheat aphids, predicting the population dynamics of aphids based on climate scenarios, as well as improving the accuracy of forecasting and scientific validity of control policy. By analyzing the typical pattern of global warming - the acceleration of daily minimum temperature, we set five temperature patterns with the same high temperature but different low temperature in order to simulate the impact of phonological synchrony shifting of wheat on the development time, longevity, fecundity, mortality of Sitobion avenae. At last we used the spatial gradients as space analogues for global warming, assessed the data of insect situation and meteorological in six areas (Xinjiang, Shanxi, Beijing, Henan, Hubei, Chongqing), presumed the aphids population dynamics under A2 and B2 scenarios based on PRECIS models. The main results displayed as follows:1 Effects of temperature patterns on the life parameters of continuous generation of Sitobion avenae was confirmed. As the acceleration of daily minimum temperature, the development time of Sitobion avenae increased as linear, especially when the initial ratio of parental generation under 22±1℃were transformed to high temperature patterns. For the same starting and ending instars, the development time of the first offspring is longer than the parental generation in identical instars because of the high temperature acclimation; however, the longevity and fecundity of parental generation are much better than the first offspring at the same temperature patterns.2 Effects of temperature patterns on the life parameters of Sitobion avenae with different starting and ending instars was confirmed. Conclusively, the longevity and fecundity of PF2 and PF3 were much better in any temperature pattern. The longevity, fecundity and survival of PF4 were not different from others under 38～19～25.5℃, but under the temperature pattern of 38～13～22.5℃, the longevity of PF4 was significantly shorter, representing a 1.55 value for the fecundity per female, and a 40% livability.3 The most suitable temperature pattern was confirmed. Among the five different temperature patterns in this experiment, the development time, longevity, fecundity, mortality were much better when under 38～19～25.5℃and significantly decreased when under the temperature patterns of 38～13～22.5℃and 38～25～28.5℃.4 Effects of growth stage of wheat on Sitobion avenae was confirmed. In anthesis (GS60～69) of wheat, the development time of Sitobion avenae is shortest, and the fecundity and mortality is the highest. Next are milk development (GS70～79), Stem elongation (GS30～33), inflorescence emergence (GS55～59). In dough development (GS 80～89) and ripening (GS 90～94), the life parameters of Sitobion avenae is significantly worse. 5 Forecast the population dynamics of wheat aphids under A2 and B2 scenarios preliminarily. When the populations of wheat aphids assess the peak in 2008, the number of aphids per tiller in Beijing, Shanxi, Xinjiang, Henan, Wuhan, and Chongqing is 315.6, 29.5, 7.9, 6.1, 1.5, and 1.3 respectively. Based on PRECIS models, under A2 scenarios, the year 2056 of Shanxi, 2037 of Beijing and 2084 of Henan will be similar to the year 2008 of Henan, Shanxi, and Wuhan, respectively, and the damage degree of wheat aphid is presumed to decrease. The year 2080 of Wuhan will be similar to the year 2008 of Beijing, and the damage degree of wheat aphid is presumed to be severe. Under B2 scenarios, the year 2078 of Xinjiang, 2093 of Henan will be similar to the year 2008 of Beijing, and the damage degree of wheat aphid is presumed to be severe. The year of 2091 of Shanxi, 2073 of Beijing will be similar to the year 2008 of Wuhan and Henan, respectively, and the damage degree of wheat aphid is presumed to decrease. Under these two scenarios, the year of 2076 and 2041 will be similar to the year 2008 of Wuhan, respectively, and the damage degree of wheat aphid is presumed to be not serious.
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