Understanding Yield Potentials and Yield Gaps for Wheat Production in China.

Estimating yield potential (Yp) and yield gap (Yg) is essential to prioritize research and formulate policies for food security. While wheat production plays an important role for Chinese food supply, current Yg for wheat hasn’t been well understood.  In this study,  we used published recorded yield, best farmers’ yield, experimental yield and farm  survey  data  to  assess  Yp  and  Yg  in  five wheat  agro-ecological  regions of  China. According to the recorded yield 547 data points at 213 sites across China form 2005 to 2013, Yp averaged 9.0 t ha^-1. The best farmers’ yield and experimental yield was 8.0 t ha^-1 and 6.2 t ha^-1, respectively. In comparison, the average farmers’ yield was 5.6 t ha^-1 based on 4552 farmers surveyed in 2007-2009. Consequently, the Yg between the average farmers’ yield and the recorded yield potential was 3.4 t ha^-1 and farmers attained 62% of the yield potential. The Yg between the average farmers’ yield and the best farmers’ yield was 2.3 t ha^-1 and farmers achieved 71% of the Yp. The Yg between the average farmers’ yield and the experimental yield was 0.6 t ha^-1 and farmers achieved 90% Yp. Meanwhile, we found the Yp and Yg varied a lot in different regions. The regional variation for Yp and Yg were due to water and climatic conditions. To close the different Yg, multidisciplinary understanding and cooperation among plant science, climate, agronomy, soil science, agro-ecology and agricultural extension, resulting in an integrated soil–crop system management, is essential.