Abstract: In this paper, we present the impacts of temperature and precipitation changing to wheat - rice production in Jiangsu province in recent 20 years, based on mathematical statistics and nonlinear regression model methods. Relative data shows that the maximum temperature(Tmax), minimum temperature(Tmin) and average temperature(Tavg) increased by 0.050,0.056 and 0.061℃ annually in recent 20 years. However, there is no obvious change in precipitation (Prec). As the climate warming, the whole growth process of winter wheat significantly reduced 0.41 d (day) (p<0.05) annually. Vegetative stage reduced 0.70 d every year. Reproductive stage extended 0.32 d significantly in each year (p<0.05). Both vegetative stage and whole growth stage of winter wheat and Tavg, Tmax, Tmin of each stage show negative correlation. Although the whole growth stage of rice pushed back integrally, the days didn't change. Comparing 2000s to 1990s, the growth stage of winter wheat was shortened, and both rice and winter wheat seeding time was delay. So replacement time of wheat-rice stubble extended 5d, while rice-wheat stubble reduced 3d. In recent 20 years, yields of wheat and rice are rising significantly (p<0.05). Annual yield significantly increased 85.5 kg·hm^-2 per year(p<0.01). By using nonlinear regression model analysis, the annual yield increased 0.47%, 0.10% and 1.92% respectively, if Tavg, Tmax and Tmin increased by 1℃, because the increasing yield of winter wheat is higher than the yield reduction of rice. In order to take advantage of the changing climate, postponing breeding to prevent vigorous growth of winter wheat before winter is suggested. Select late varieties with high-temperature tolerance to promote the reproductive growth would also help increasing the production of rice.

Key words: climate warming, winter wheat, rice, growth period, yield