关键词: 粳稻；氮肥；产量；氮肥利用率

Abstract:

A field trial was conducted in Dangyang City to compare the yield and nitrogen (N) use efficiency of 2 japonica rice varieties (Zhongdao 1 and Huaidao 5) in the hilly land of central Hubei Province (single\|cropping indica rice area) under different N levels. The results showed that the grain yield of the treatments with N were increased averagely by 2 179 kg/hm2 and 3 209 kg/hm2, and the increase rates were 45.6% and 53.5%, respectively.  Linear and platform correlations had been shown between yield and N fertilizer amount. The platform yields of “Zhongdao 1” and “Huaidao 5” were 7 517 kg/hm2 and 10 234 kg/hm2, respectively. The most suitable N application amount were 221.0 kg/hm2 and 235.5 kg/hm2, respectively. Compared with N0 treatment, the N uptakes by these 2 japonica rice varieties were averagely increased  58.7 kg/hm2 and 71.8 kg/hm2, and the increase rates were 80.9% and 85.2%. When the N application amount was 248 kg/hm2, the N recovery efficiency (NRE), N agronomic efficiency (NAE), N contribution rate (NCR) and partial factor productivity of applied N (PFPN) of the 2 varieties were 29.4% and 37.6%, 10.6 kg/kg and 18.0 kg/kg, 35.4% and 42.6%, 29.8 kg/kg and 42.3 kg/kg. The result of comprehensive analysis  believed that “Huaidao 5” could get a higher yield and high N use efficiency when planted in the hilly land of central Hubei Province.

Key words: japonica rice, nitrogen fertilizer, yield, nitrogen use efficiency