Abstract:In order to reveal the influence of the mix ratio between slow released urea (SRU) and ordinary urea on the nitrogen (N) translocation and soil mineral nitrogen accumulation of post-anthesis wheat, the effect of N managements of control (CK), conventional (Ncon), optimized (Nopt), different mix ratios of SRU to urea (SRU1、SRU2、SRU3), and only urea (SRU4) on post-anthesis N translocation, yield, nitrogen use efficiency (NUE), soil NO3--N and NH4+-N accumulation of wheat was investigated via field experiments between the mixed soil and yellow-brown soil corresponding to the wheat-maize and wheat-rice rotation distributed over Anhui province. Results showed that the yield, the amount of post-anthesis N accumulation and translocation in mixed soil were higher than those in yellow-brown soil under the same treatment, which increased by 71.8%, 199.1% and 25.8% on average, respectively. However, N translocation rate and apparent surplus amount of soil mineral N decreased by 16.1% and 49.7% on average in mixed soil than those in yellow-brown soil, respectively. Compared to the Ncon, yield showed no obvious differences, but NUE was significantly higher under the treatments of SRUs, which increased by 43.7%~91.9% and 6.6%~26.9% between mixed soil and yellow-brown soil. The highest NUE was under the treatment of SRU2 (ratios of SRU to urea 2:1). Compared to the Nopt, NUE increased at significant level only under the treatment of SRU2 in mixed soil. There was more soil NO3--N and NH4+-N accumulation in 0-30 cm soil layer in Ncon than in SURs in post-anthesis of wheat, while the accumulation soil mineral N showed similar trend. The results showed it decreased accumulation soil mineral N under the treatments of SRUs in the late growth period of wheat with higher wheat yield and NUE. Therefore, one-time applying of the mix of SRU to urea could improve wheat yield, and reduce environmental pollution risk.