Management Systems for Improved Yields and Yield Stability with Climate Variability in China.

Management systems for improved yields and yield stability with climate variability in China 

Rongrong Zhao¹, Ping He¹, Adrian Johnston²

1 Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, International Plant Nutrition Institute China Program, Beijing China 100081; International Plant Nutrition Institute, Saskatoon, S7N 3A3 CANADA 

The growing demand for agricultural production has been driven by the great pressure of world population since the “Green Revolution” started. Old intensification agricultural system could not ecologically and sustainably satisfy increasing food demand and environmental negative effects. Field experiments based on ecological intensification (EI) concept in Jilin province (mono-cropping, rainfed spring maize) and Hebei province (double cropping, irrigated summer maize and winter wheat) were conducted to explore crop management combinations under different climate conditions during 2009 to 2014. EI treatment was averagely applied with 180-75-90 kg N-P₂O₅-K₂O ha^-1 for spring maize and 186-64-76 kg N-P₂O₅-K₂O ha^-1 for summer maize, and FP was applied with 251-145-100 kg N-P₂O₅-K₂O ha^-1 for spring maize and 240-121-17 kg N-P₂O₅-K₂O ha^-1 for summer maize. All secondary and micronutrients were amended based on soil testing. Results indicated that the average grain yields were 11.8 t ha^-1 and 8.7 t ha^-1 in EI treatments, or 92.6% and 86.8% of the yield potential in rainfed and irrigated maize, higher than the FP treatment with mean yield of 11.4 t ha^-1 and 8.1 t ha^-1 across six-season. At the same time, the EI treatment saved N application rate and thus improved the nitrogen efficiencies. Higher AE_N, RE_N and PFP_N in EI treatment (39.7 kg kg^-1, 66.1% and 66.2 kg kg^-1 for spring maize, and 9.9 kg kg^-1, 31.8% and 50.4 kg kg^-1 for summer maize) were observed than those in FP treatment (26.9 kg kg^-1, 42.5% and 50.4 kg kg^-1 for spring maize and 6.3 kg kg^-1, 15.9% and 33.0 kg kg^-1 for summer maize). The higher and stable yield obtained from EI was from right crop hybrid, best nutrient management (right fertilizer source, right time, right rate and right placement) and other agronomic practices including plant density and water management.