In 2011 and 2012, plot experiments with the same N rate as panicle (35 kg·hm-2 ) were conducted to elucidate the effect of N rate as basal and tillering fertilizer ( NBT) on yield and N fertilizer use efficiency. N rates as basal and tillering fertilizer were 0, 30, 65, 85 and 115 kg·hm-2, respectively. Dry matter accumulation, N uptake, N fertilizer use effi-ciency and yield of rice were measured. The results showed that there were positive correlation between NBT and dry matter ac-cumulation or N uptake before heading stage or jointing stage (P<0. 05);correlations between NBT and dry matter accumula-tion or nitrogen accumulation after heading or from heading to maturation were explained by quadratic curve significantly ( P<0. 05), so too high NBT couldn't increase the dry matter accumulation and nitrogen uptake after heading. There were quadratic curve relationship between NBT and rice yield. The harvest index and N fertilizer agronomic efficiency firstly increased, then decreased with the increase of NBT. The NBT and nitrogen uptake efficiency or partial factor productivity of applied N showed an obviously negative correlation ( P<0. 05 ) . Yield and N uptake was higher in the 2012 than 2011 due to higher tempera-ture. Appropriate NBT was about 64 kg·hm-2 in the soil with medium fertility. Although rice yield didn't decreased with in-crease of NBT, nitrogen use efficiency was reduced because of higher N loss. Appropriate NBT was the key of high yield com-bined with high nitrogen efficiency.%在固定穗肥氮量(35 kg·hm-2)的条件下,研究基蘖肥氮量与寒地水稻产量和氮效率的关系.2011~2012年,设置基蘖肥氮量分别为30、65、85和115 kg·hm-2的处理,并以不施氮为对照.测定了主要生育期水稻干物质、 氮积累、 产量和氮效率.结果表明:随着基蘖肥氮量的增加,水稻抽穗期前或拔节前的干物质积累量和氮积累量也相应增加,两者为显著的正相关;成熟期干物质积累量、 氮积累与基蘖肥氮量呈显著的二次曲线关系,基蘖肥氮量太高反而不利于后期干物质和氮素积累;水稻产量和基蘖肥氮量呈二次曲线关系,收获指数亦随氮肥用量增加呈先增加后减小的趋势;氮素吸收效率、 氮肥偏生产力和基蘖肥氮量呈显著负相关关系.2012年温度较高,因此产量和总氮积累均高于2011年.在试验的土壤条件下,平均基蘖肥氮量为64 kg·hm-2较为适宜,基蘖肥用量增加虽没有造成减产,却使氮素大量损失,使氮效率降低,适宜的基蘖肥氮量是水稻高产和氮素高效利用的关键.
展开▼
