Estimating a new approach of fertilizer recommendation across small-holder farms in China

•Nutrient Expert for Hybrid Maize (NE) decision support system has been built for smallholder farms in China.•NE used 4R nutrient stewardship and based on yield response and agronomic efficiency.•NE reduced apparent nitrogen losses and maintained grain yield through improvement of nutrient management.•NE can be used with or without soil testing and experimental data from every field. Over and imbalanced fertilization has caused a series of environmental problems and threaten the food security in China. On-farm experiments were conducted from 2010 to 2012 at 408 sites in seven provinces to evaluate a new fertilizer recommendation approach, Nutrient Expert (NE) for Hybrid Maize (Zea mays L.), to meet the requirements of nutrient management for small-holder farms in China. Compared with the current farmers’ fertilizer practices (FP), NE maintained grain yield and profitability, but decreased 30.4% of nitrogen (N) fertilizer (68kg Nha−1) and 11.3% of phosphorus (P) fertilizer (7kg P2O5ha−1), while potassium (K) fertilizer rate increased by 38.8% (19kg K2Oha−1). NE increased agronomic efficiency of applied N (AEN) by 47.0%, N recovery efficiency (REN) by 51.0%, and partial factor productivity of applied N (PFPN) by 35.5%. More importantly, NE decreased by 21.5 and 49.7kgha−1 of apparent N loss for summer maize and spring maize as compared with FP, respectively. The differences in agronomic and environmental parameters between NE and FP confirmed that the Nutrient Expert for Hybrid Maize is a promising nutrient decision support tool which not only increasing grain yield, nutrient use efficiency and profit, but also reducing nutrient loss and environmental pollution.