施氮量对酿造高粱产量和氮素利用率的影响

Effects of Nitrogen Application Rate on Yield of Brewing Sorghum and Nitrogen Use Efficiency

为了实现酿造高粱氮肥合理高效利用,以晋杂22号为试验品种,研究了6种氮肥施用量(0,75,150,225,300,450 kg/hm^2)对酿造高粱产量和氮素利用率的影响。结果表明,在施氮0~450 kg/hm^2,施用氮肥有效地增加了高粱产量和净利润,但随着施氮量的增加产量先升高后降低,其关系可表示为y=-0.037x^2+17.759x+5 874.41(R2=0.878 1)。随着施氮量的增加高粱氮肥偏生产力和氮肥利用率显著降低;氮素吸收效率逐渐降低;氮素利用效率大体呈下降趋势;当施氮量为225 kg/hm^2时,高粱产量、净利润最大,极显著高于不施氮处理,增产率达37.64%;氮肥农学利用率和氮肥偏生产力分别为9.96,36.42 kg/kg,氮肥利用率可达到38.70%,且氮平衡为3.07,大体上满足氮素平衡。综合分析各项指标,施氮量为225 kg/hm^2是酿造高粱晋杂22号实现高产、高效益、较高氮肥利用率的适宜氮量。

To realize rational and effective use of N fertilizer in brewing sorghum,a field trial with a brewing sorghum variety Jinza 22 was conducted to study the effects of different N fertilizer rates（0,75,150,225,300,450 kg/ha）on yield of brewing sorghum and nitrogen use efficiency.The results showed that nitrogen application increased effectively grain yield and net profit of sorghum in the range of 0-450 kg/ha N applied,but grain yield increased and then decreased with the increased of nitrogen application.The relationship between yield and N fertilizer rates could be expressed as y=-0.037x2＋17.759x＋5 874.41（R2=0.878 1）.With the increased of N application,N partial factor productivity and N fertilizer use efficiency significantly decreased,N absorption efficiency gradually reduced and N use efficiency had a largely down trend.The highest yield and net profit were obtained by the N treatment of 225 kg/ha（N225）.Compared with the treatment of no nitrogen application,yield of N225 was increased extremely significantly with the rate of yield increased of 37.64%,N agronomic efficiency of 9.96 kg/kg,N partial factor productivity of 36.42 kg/kg,N fertilizer use efficiency of 38.70% and N balance of 3.07 which kept roughly the N balance.Comprehensive analysis of the indicators,N fertilizer application rate of 225 kg/ha is the optimum level for high-yield,high-income and relative high-N use efficiency of sorghum variety Jinza 22 under the experimental condition.