Abstract: Based on a 29-year(1981-2009)field fertilization experiment and a 4-year(2006-2009)nutrient depletion pot experiment,effects of long-term fertilization regimes on crop productivity and stress resistance of the double rice cropping system in the hilly area south to the Yantze River were analyzed.Results show that Treatmnent NPK+OM(application of inorganic NPK plus organic manure)was the highest in productivity of both rice crops and annual field productivity and its annual mean aboveground biomass and mean grain yield was 24.5% and 20.0% higher than Treatment NPK,respectively.Treatment NPK significantly increased N use efficiency,where as Treatment NPK+OM did even more.Treatment N and Treatment NPK displayed a delining trend in annual grain yield with a magnitude being 43.7 and 1.8 kg·hm^-2·a^-1,respectively,while Treatment NPK+OM showed an increasing trend with a range of 6.9 kg·hm^-2·a^-1.Balanced feritilization(Treatment NPK and Treatment NPK+OM)significantly decreased the coefficient of variations of crop biomass and grain yields and increased the sustainable yield index(SYI),resulting in the high stability of crop pro ductivity of the double rice cropping system.After the 4-year nutrient depletion experiment,the treatments basically followed the order of NPK+OM>NPK>N in aboveground biomass and grain yield of each rice growing season and the whole year.During the experiment,Treatment NPK+OM remained at the top in mean aboveground biomass and mean grain yields,indicating that long-term application of NPK plus organic manure may improve tolerance of the paddy soil to nutrient depletion.In conclusion,such a fertilization pattern can not only sustain high productivity of the double rice cropping system,but also enhance the system’s resistance to environmental stresses,which contributes to sustainable high and stable production of the double rice cropping system in the hilly area south to the Yangtze River.

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mso-bidi-language: AR-SA, mso-bidi-font-family: 宋体" lang="EN-US">Long-term experiment, fertilization regime, hilly area south to the Yangtze River, paddy field, productivity, stress resistance