Abstract:In order to further investigate the uptake of fertilizer-N at different growth stages and in the partitioning of accumulated N in transplanted rice, field experiments were combined with micro-area test, and the traditional flooding irrigation was used as control, three N rates (85kg/hm2,110kg/hm2 and 135kg/hm2) were set and three 15N-labelled fertilizer application treatments were conducted in rice with different fertilizer-N recovery efficiencies. The fertilizer-N recovery efficiency of total fertilizer was measured, and the fertilizer-N recovery efficiencies of basal, tillering and panicle fertilizations were analyzed by applying 15N-labelled urea as basal, tillering or panicle fertilizer, and comparative study of the two kinds of irrigation fertilizer at different nitrogen utilization rates. The result showed that compared with the traditional flooding irrigation, rice irrigation control model significantly increased dry matter accumulation, nitrogen accumulation and yield of rice, had the “water-saving and high-yield” role. About 16.49%~22.23% of different nitrogen amounts of total nitrogen accumulation in rice under nitrogen fertilizer, the difference between different irrigation methods was not significant;the difference between different irrigation methods was not significant;different nitrogen levels control irrigation rice total fertilizer-N recovery efficiency was 31.82%~36.29%, the fertilizer-N recovery efficiency of basal fertilizer was 10.91%~15.36%, the fertilizer-N recovery efficiency of tillering fertilizer was 34.84%~36.90%, the fertilizer-N recovery efficiency of pancile fertilizer was 55.78%~63.85%. The rice control irrigation mode in addition to fertilizer-N recovery efficiency of basal fertilizer in rice were lower, total, tillering and panicle fertilizer-N recovery efficiency was better than those of the traditional flooding irrigation. The correlation analysis showed that fertilizer-N recovery efficiency of total fertilizer had a significant positive correlation with fertilizer-N recovery efficiency of tillering fertilizer and panicle fertilizer, which provided a reference for further improving the utilization rate of fertilizer nitrogen under controlled irrigation.
