Effects of combined application of common urea and controlled-release urea on foxtail millet yield and nitrogen utilization
To uncover the physiological and ecological mechanisms by which controlled-release urea in regula-ting grain growth,and nitrogen uptake and utilization in dryland conditions,a field experiment was conducted with a foxtail millet variety of'Shanyugu 3'in the semi-arid,rain-fed agricultural region of northern Shaanxi Province from 2022 to 2023.The study included 6 treatments:no urea(CK),100％common urea(F1),100％controlled-release urea(F2),50％common urea+50％controlled-release urea(F3),70％common urea+30％controlled-release urea(F4),30％common urea+70％controlled-release urea(F5).The total nitrogen of fertilizer treatment was 135 kg·hm-2.The effects of common urea and controlled-release urea combined application on the growth and development of foxtail millet,dry matter accumulation,yield,nitrogen uptake and utilization were studied.The re-sults showed that when the proportion of controlled-release urea was 30％～50％,the performance of foxtail millet indexes was better than other treatments.Compared with the conventional fertilizer F1 treatment,when the ratio of controlled-release urea was 30％～50％,the SPAD value of leaves at grain filling stage was increased by 0.65％～3.20％,the net photosynthetic rate Pn was increased by 1.07％～4.33％,the total dry matter accumulation at matu-rity was increased by 14.53％～77.27％,and the yield was increased by 29.28％～31.81％.Nitrogen utilization rate,nitrogen partial productivity and nitrogen agronomic utilization rate were increased by 9.67％to 55.47％,9.72％to 66.74％and 43.04％to 295.55％,respectively.In conclusion,when the total nitrogen fertilizer applica-tion is 135 kg·hm2,common urea combined with 30％～50％controlled-release urea is advantageous for the growth and development of foxtail millet in dry farming conditions in northern Shaanxi Province.
foxtail milletureacombined applicationdry matter accumulationyieldnitrogen use efficiency
万方数据
维普
