As supplement nitrogen application at booting stage, nitrogenefficiency was the lowest.
孕穗期追施氮肥，氮效率最低。
2
Diversified nitrogenefficiency is lower in 2000 than in 1999, which show that nitrogen effectiveness is not manifest, even with negative effectiveness.
Based on the results of correlation analysis, nitrogen absorption efficiency contributed more to the nitrogenefficiency than nitrogen utilization efficiency.