Abstract: A field experiment was conducted in the Taihu Lake region of southern Jiangsu to study the effects of applying  nitrogen (N) fertilizer and fertilizer additive on the rice yield and the rice plant N uptake, translocation, and utilization. Applying  N fertilizer had significant positive effects on the rice yield, accumulative absorbed N at all growth stages and at each growth stage, and N translocation rate after anthesis (P<0.01). However, when the N application rate exceeded 200 kg·hm^-2, its yield-increasing effect was not significant (P>0.05). The N translocation rate after anthesis and the N fertilizer use efficiency decreased with increasing N application rate. Applying fertilizer additive further improved the rice yield, accumulative absorbed N, N translocation rate after anthesis, and N fertilizer use efficiency, and this effect was more evident when the N application rate was equal to or greater than 200 kg·hm^-2. Relatively high rice yield and N use efficiency were achieved when applying 150 kg·hm^-2 of  N fertilizer without the application of fertilizer additive.

Key words: rice, nitrogen application rate, fertilizer additive, yield, accumulative absorbed nitrogen, nitrogen translocation, nitrogen fertilizer use efficiency