Abstract:The impact of zeolite (Z) on the dynamic of soil available potassium in the rice production system remains unknown, especially in the alternate wetting and drying (AWD) irrigation rice production system. To explore the application potential of zeolite in alternate wetting and drying rice system, a 2-year experiment was conducted to determine the effects of Z on grain yield and soil available potassium under different Z application rates and irrigation methods using the split plot design. A Japonica rice (cv. Shen Dao 529) was cultivated in brown loam soil. Treatments included 2 irrigations methods (CF: continuously flooded irrigation, AWD: alternate wetting and drying irrigation) as main plots and 3 zeolite application rates (0, 5, and 10 t/hm2) as sub-plots within each of main plots. The experiment was repeated in 2018 but Z was not applied, and the plots in 2018 experiment were same as 2017 experiment. The results showed that Z application at the rate of 10 t/hm2 significantly increased grain yield as compared with no zeolites, in particular Z application at the rate of 10 t/hm2 in the AWD rice production system, of which the yield was 8.7%-22.3% higher than the zeolite-free treatment in the CF rice production system. Zeolite had a significant positive effect on the surface soil available potassium content, and above-ground dry matter accumulation as well as the K accumulation of rice plants in the rice field. Z application at the rate of 5-10 t/hm2 increased the surface soil available potassium content in the basel fertilizer stage, tiller fertilizer stage and panicle fertilizer stages, above-ground dry matter accumulation in later tillering stage, jointing-booting stage, heading-flowering stage, milky ripening stage, and yellow ripening stage and improved the aboveground K accumulation of rice plant in the later tillering stage, jointing-booting stage, heading-flowering stage, milky ripening stage, yellow ripening stage. The positive effects of Z observed were even more obvious when applied into the AWD rice production systems relative to the CF one. Compared with the most commonly used treatment (CF and Z-free treatment), the AWD irrigation in combination with 10 t/hm2 Z application average increased the surface soil available potassium content in the basal fertilizer stage, tiller fertilizer stage and panicle fertilizer stages, above-ground dry matter accumulation in Jointing-booting stage, heading-flowering stage, milky ripening stage, Yellow ripening stage (except later tillering stage) and improved the aboveground K accumulation of rice plant in the later tillering stage, jointing-booting stage, heading-flowering stage, milky ripening stage, yellow ripening stage by 11.81%-21.42% in 2017 and 9.69%-23.79% in 2018. The rice yield component results revealed the increased yield in Z treatment was mainly caused by increased effective tiller number at harvest, while path analysis of dynamics in average soil available potassium at different fertilization stages and above-ground K accumulation of rice plants at different growth stages further suggested that the increased grain yield in zeolite treatment was mainly due to increase of soil available potassium content in tiller-panicle fertilizer stage and panicle fertilizer-harvest stage caused by increased zeolite, and increased aboveground K accumulation of rice plant in the heading-flowering stage and yellow ripening stage. In addition, these positive residual activities could maintain for at least 2 years after initial application in both the CF and AWD rice production systems.