Abstract: 【Objective】 Effects of long-term fertilization on rice yield and its stability of double cropping rice system was studed in this paper.【Method】 Fertilization, environment and their interactions were analyzed by AMMI (additive main effects and multiplicative interaction) model based on a 25-year long-term fertilizer experiment conducted in yellow clayey soil in Nanchang of Jiangxi Province. At this site, 8 treatments were established in 1984. They were in a early rice late rice rotation receiving no fertilizer(CK)，nitrogen fertilizers deficiency (PK), potassium fertilizers deficiency (NP), phosphorus fertilizers deficiency (NK), balanced chemical fertilizers application (NPK), substitution of 70% inorganic N by 30% organic N in balanced chemical fertilizers application (70F+30M), substitution of 50% inorganic N by 50% organic N in balanced chemical fertilizers application (50F+50M)，substitution of 30% inorganic N by 70% organic N in balanced chemical fertilizers application (70F+30M).【Result】Two main results obtained from this analysis showed as follows. Firstly, the sum of squares of fertilization treatments by environment interactions (F×E) was 9.78% of total sum of squares, and achieved a significant difference at 1% level from AMMI model analysis, from which IPCA1, IPCA2, IPCA3 explained 88.46% sum of squares of the interactions. Coefficients of correlations which were significant correlations between the stability parameters and Shukla coefficient of variation or coefficient of variation were 0.97 and 0.83. Secondly, balanced chemical fertilizers application (NPK) treatment could be good for improving the rice yield and its stability of double cropping rice system. Partial substitution of chemical fertilizers by organic manure made further improvement in rice yield and its stability under the equal nutrient amount application condition, compared with NPK treatment. The yields of substitution application of 30%, 50% and 70% of chemical fertilizer by organic fertilizer treatments increased by 6.15%, 3.88%, and 7.75%, respectively, and rice yield stability increased by 25.91%, 59.78%, and 29.31%, respectively. 【Conclusion】 The AMMI model clearly explained the interactive effects of fertilization treatments across environment (F×E). It was a good method for evaluating stability of double cropping rice yield under long-term fertilization. It was concluded that combined application of organic manure and chemical fertilizers was the best fertilization on achieving high and stable yield of double cropping rice in the region. Stability of the treatment combined application of 50% organic manure combined with 50% chemical fertilizers was the best under relatively high yield conditions. Treatments combined application of 30% or 70% organic manure with 70% or 30% chemical fertilizers obtained the highest yield and the best adaptability under the more stable circumstances.

Key words: double cropping rice , long-term fertilization, AMMI model, stability of yield