Global Maize Project in China: Liufangzi, Gongzhuling, Jilin Province

This long-term field experiment was initiated in 2009 in Liufangzi, Gongzhuling City, Jilin Province, to investigate the performance of ecological intensification (EI) practices to improve yield over time at a faster rate than common farmer practice (FP), while minimizing adverse environmental impacts. The main plots consisted of two treatments: EI (180-75-90-20-5 kg N-P₂O₅-K₂O-S-Zn/ha) and FP (251-145-100 kg N-P₂O₅-K₂O/ha). Three split plots included: 1) N applied in all years (N all yr); 2) N applied in 2 of every 3 years (N 2/3 yr); and 3) no N applied any year (N 0 yr). The site represents a typical spring maize mono-cropping system for the province. The crop was planted on May 9 and harvested on September 30, 2010.

An average grain yield of 11.1 t/ha was obtained in the EI treatment, which was 273 kg/ha lower (not significant) than FP. Agronomic efficiency (kg grain yield increase per kg N applied) was 31.4 kg/kg in the EI treatment and 23 kg/kg in the FP treatment. Partial factor productivity (kg grain yield per kg N applied) was 61.6 kg/kg with EI and 45.3 kg/kg with FP. Although a marginal yield decrease was observed in the EI treatment in 2010, both profitability and N use efficiency were still improved. IPNI-20