Effect of One-off Fertilization at Different Growth Stages on Yield and Nitrogen Fertilizer Efficiency of Summer Maize
To clarify the suitable one-off fertilization stage for coated urea 1∶1 with normal urea.The effects of no N application(CK),simultaneous application of fertilizer and sowing(T1),one-time fertilizer application at the fifth leaf stage(T2)and one-off fertilization at the tenth leaf stage(T3)on the growth and development,N accumula-tion and transport,and yield of summer maize were investigated.The results showed that T1 treatment in Hebi and Yuanyang had the highest yield of 12 700 kg/ha and 10 945 kg/ha,respectively,but the difference between them and T2 treatment was not significant,and by 14.2％and 10.9％compared with T3 treatment;dry matter accumula-tion increased by 5.6％-25.1％and 1.6％-21.2％compared with other treatments.The highest SPAD values and leaf area index were reached in T1 leaves at different growth stages.In Hebi and Yuanyang,the highest N apparent utilization efficiency was 35.2％and 35.5％under T1 treatment,which increased 5.6-14.7 and 3.2-13.6 percentage points compared with other treatments.N accumulation increased 13.8％-34.5％and 14.5％-41.5％compared with other N application treatments.Soil dependency rate was lower under T1 treatment than T2 and T3.In conclusion,the simultaneous application of fertilizer and sowing improved maize yield,N fertilizer efficiency,leaf SAPD value and leaf area index,maintained high N uptake rate,reduced soil N dependency rate,met the N demand of maize throughout the reproductive stage,and achieved high yield and efficient fertilization of summer maize.
NETL
NSTL
万方数据
