The rice production practices of high yield and high nitrogen use efficiency in Jiangsu, China

To face the great challenges of ensuring food security and environmental sustainability, agricultural production must be improved by high yield and high resource utilization efficiency (HYHE). We recently addressed this challenge and evaluated yield potential by surveying 735 farmers in 2008-2012 and then conducting 6 rice field experiments in 2008-2013 with large demonstration areas in 2010-2013 aimed to actualize the HYHE in Jiangsu Province, China. The survey result showed that the averaged N rate, grain yield and N partial factor productivity (PFP_N) of the farmers were 336.7 kg ha^-1, 8131.8 kg ha^-1 and 24.2 kg kg^-1, respectively. Through controlling total N rates and adjusting the application timing, the yield and the PFP_N of optimal N managements (OPT) were increased by 5.9% and 37.6% with 31.4% reduction in N supply amounts for 6 experimental sites, and the yield increased by 5.6% for large demonstration areas compared with farmers' fertilizer practices (FFP), respectively. In conclusion, although the soil properties of the different regions varied, HYHE could be achieved by regulating the N management practices, thus contributing to higher rice production and lower environmental costs from intensive agriculture in Jiangsu, China.