Abstract: This paper studied the effects of applying ammonium nitrate solution (UAN) in summer maize (Zea may L.) by taking a field experiment. The results showed that compared with urea, applying UAN at the same nitrogen amount could increase the yield of summer maize, which mainly attributed to the increase of kernels per ear. The yield of UAN treatment of 80% optimized nitrogen amount was decreased, but was still higher than urea treatment of optimized nitrogen amount. The output and net income of summer maize of UAN treatment at the same or 80% nitrogen amounts were higher than those of urea treatment, and the contents of crude protein and starch were also improved. Nitrogen uptake efficiency, nitrogen apparent recovery efficiency, nitrogen agronomic efficiency and nitrogen production efficiency were also higher than those of urea treatment. However, compared with urea, applying UAN at the same nitrogen amount had the likelihood of nitrate leaching, but the rate of nitrate leaching under UAN treatment at reducing nitrogen amount was decreased. Applying UAN at the same nitrogen amount could also raise water use efficiency of grain kernel and above ground part in summer maize, but those of the reducing application of UAN were decreased to varying degrees. In conclusion, the effect of applying UAN was better than that of urea in summer maize, according to comprehensive consideration of yield, economic benefit, nitrogen use efficiency and water use efficiency.

Key words: ammonium nitrate solution, maize (Zea may L.), yield, quality, nutrient uptake

摘要： 采用大田试验，研究了尿素硝酸铵溶液（UAN）在夏玉米上的施用效果。结果显示：与尿素相比，同等施氮条件下，施用UAN可提高玉米产量，主要归因于穗粒数的增加；优化施氮量减量20%施用，玉米产量有所降低，但仍高于尿素优化施氮量处理。同等施氮或减氮20%条件下，施用UAN的产值和经济效益也均高于尿素处理，籽粒粗蛋白和淀粉含量也有提高。玉米籽粒氮、磷含量和累积量，秸秆中磷含量和累积量也显著增加；氮素吸收效率、氮素表观回收率、氮素农学利用效率和氮肥生产效率也高于尿素处理。同等施氮量处理，施用UAN较尿素土壤硝态氮有向地下淋洗的趋势，减量施用，硝态氮向地下淋洗的速率减慢。和尿素相比，施用UAN还可提高玉米籽粒和地上部水分利用效率，减量施用，水分利用效率有所下降。综合而言，从产量、经济效益、氮肥利用效率和水分利用效率来看，施用UAN的效果好于尿素。

关键词: 尿素硝酸铵溶液, 玉米, 产量, 品质, 养分吸收