Changes in the efficiency of fertiliser use in China

Results of three nationwide fertiliser efficiency studies in recent history in China are reviewed. The results indicate that after a long history using organic recycling to maintain soil fertility in China, nitrogen (N) became the first yield-limiting nutrient in the first national fertiliser efficiency study in 19351940. With N fertilisation being used, phosphorus (P) and potassium (K) deficiencies were gradually revealed and developed in the following national fertiliser efficiency studies in 19581962 and 19811983. Research conducted through the International Plant Nutrition (IPNI) cooperative network in China in 20002006 indicates that agronomic efficiencies of N fertiliser (yield increase per kilogram from the application of 1 kg N) for rice, wheat and maize are 11.7 kg, 10.8 kg and 12.2 kg grain per kilogram of N, respectively, while crop recovery efficiency of N (percentage of N taken up by plant in total N applied) with rice, wheat and maize were 24.8%, 35.7% and 30.5%, respectively. Both agronomic efficiency and crop recovery efficiency of N are significantly lower than the average N use efficiency reported in international literature for other countries. Current agronomic efficiency of P and K are also discussed. Measures to improve fertiliser use in China are discussed. Copyright (c) 2012 Society of Chemical Industry