The aims of this study were evaluating the impact of mixed applying controlled-release urea and conventional urea on matter accumulation

nitrogen uptake and migration

and grain yield of spring maize

and improving the high yield and high efficiency cultivation techniques in southern Ningxia area. And this study could provide theoretical and technical reference to scientific nitrogen management techniques for spring maize in arid and semi-arid rainfall-fed region. Xianyu698 taken as experiment subjects were grown in controlled environments with two nitrogenous fertilizers (controlled-release urea (CRU ) and conventional urea ( U)) in four treatments (T1: applying U as basal fertilizer by N150 kg/hm2 + U topdressing at V12 by N75 kg/hm2; T2: CRU as basal N75 kg/hm2 + U as basal N75 kg/hm2+ U topdressing at V12 N75 kg/hm2; T3: CRU as basal N 150 kg/hm2+U as basal N 75 kg/hm2; T4: CRU as basal N 225 kg/hm2). The treatment without applying nitrogen fertilizer was CK. The results showed that when applying the same amount of nitrogen

compared to conventional urea treatment (T1)

reasonable mixed application of controlled-release urea and urea as basal fertilizer (T3) could significantly increase maize yield by 12.63%

and this were mainly due to extremely enhancement of grain number per spike. Reasonable increasing the ratio of controlled-release urea in basal fertilizer could promote the accumulation of dry matter at post-anthesis and the whole growth period

and increase the absorption and accumulation of nitrogen in vegetative organs and grains of maize. The study also found that applying controlled-release urea was favorable to enhance nitrogen agronomic efficiency

nitrogen use efficiency and fertilizer contribution ratio

and the effect of T3 was the best. The nitrogen agronomic efficiency and fertilizer contribution ratio of T3 were 52.12% and 22.96%

35.39% and 20.53% higher than those of T2 and T4

respectively. This study indicated that it was appropriate to applying reasonable mixed controlled-release urea (two-thirds of the total amount of nitrogen fertilizer) and conventional urea (one-third of the total amount of nitrogen fertilizer) as basal fertilizer.