Yield and N use efficiency of a maize–wheat cropping system as affected by different fertilizer management strategies in a farmer's field of the North China Plain

• N application to wheat and maize in the NCP may be reduced by up to 50%.
• In the NCP, wheat is more dependent on N application compared to maize.
• Previous fertilization practices severely affect short term N use efficiency.

This study aimed to identify whether nitrogen (N) use efficiency in a summer-maize/winter-wheat double-cropping system of the North China Plain (NCP) could be increased by adjusting N supply to crop N demand, and through the use of alternate N fertilizers and application strategies. In a static experiment conducted on a farmers’ field six reduced N treatments were compared to farmers’ practice (FP: 550 kg (N) ha−1 a−1) and a control treatment (CK).With few exceptions of single treatments in single cropping-seasons, the optimized fertilization of N did not lead to a yield reduction of either summer-maize or winter-wheat. The grain yield of summer-maize ranged between 5.8 and 7.1 Mg ha−1. The grain yield of wheat ranged between 4.4 and 6.2 Mg ha−1.For the first two vegetation periods of summer-maize, the recovery efficiency (REN: 0.09–0.30 kg kg−1) and agronomic efficiency of N (AEN) were mainly affected by the yield achieved in the control treatment (5.7 and 5.9 Mg ha−1), which was not significantly reduced compared to most fertilized treatments. In the third vegetation period of summer-maize, an increase of REN of the reduced treatments (0.37–0.58 kg kg−1) was determined compared to FP (0.21 kg kg−1). In both vegetation periods of wheat REN of the reduced treatments (0.34–1.0 kg kg−1) was significantly higher compared to FP (0.26 and 0.27 kg kg−1). The highest cumulated AEN, as well as cumulated grain yields were observed when ammonium sulphate nitrate + 3,4-dimethylpyrazolephosphate (ASNDMPP) was applied according to crop N demand and residual soil mineral N. The highest REN was observed when urea ammonium nitrate was applied in a shallow, banded depot (UANDEP).This research demonstrates that N application rates in a maize/wheat double cropping system may be significantly reduced compared to common farmers’ practice, without negatively affecting grain yield, thereby increasing N use efficiency.