Effect of different types of nitrogen fertilizer on nitrogen absorption and utilization of summer maize (Zea mays L.)

The effect of three types of nitrogen (N) fertilizers, urea (U), coated urea (CU) and compound fertilizer (CF), on N absorption and utilization efficiency of summer maize ZD958 (compact-type) and ND108 (semicompact-type) was studied in Wuqiao Experimental Station in two consecutive years to provide theoretic and practical guidance to high-yielding and high-efficiency cultivation of summer maize in North China Plain. The results showed that with the increment of N application rate, N accumulation amount (NAA) was increased significantly (P＜0.05), N uptake efficiency (NUPE), N physiological efficiency (NPE), N utilization efficiency (NUTE) and N harvest index (NHI) were decreased (P＞0.05), and N use efficiency (NUE) and N fertilizer efficiency (NFE) were decreased significantly (P＜0.05). N absorption and utilization efficiencies of summer maize were affected by type of N fertilizers. NUE and NUPE in CU and CF treatments were higher than those in U treatments. NHI in U treatments was generally higher, but the effects of cultivar, year and N rate were all significant. Genotype differences were found for NAA, NHI and NFE, with ZD958 being higher than ND108. The two cultivars belonged to sensitive type and the sensitivity of ZD958 was greater than that of ND108. These results showed N rate was the key factor to N utilization efficiency in summer maize, and choosing suitable types of cultivar and N fertilizer could also play positive roles to a certain extent. It is concluded that selecting compact-type maize and compound fertilizers can increase N utilization efficiency of summer maize in North China Plain, based on the results of this study.