Abstract: 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.

Key words: Brewing sorghum, Nitrogen application rate, Yield, Nitrogen use efficiency

CLC Number: 

• S514

• S143.1