Effects of controlled-release fertilizer on rice grain yield, nitrogen use efficiency, and greenhouse gas emissions in a paddy field with straw incorporation

Abstract The incorporation of crop straw to cropland is increasingly being recommended due to its ability to improve soil fertility. Controlled-release fertilizer could enhance nitrogen (N) use efficiency and crop grain yield in a rice–wheat rotation cropping system. The effects of controlled-release fertilizer with wheat straw incorporation on rice grain yield and greenhouse gas (GHG) emissions is poorly understood. Four treatments, i.e., chemical fertilizer (CF), chemical fertilizer with straw incorporation (CF + WS), controlled-release urea with straw incorporation (CRU + WS), and no fertilizer (C), were applied to investigate the effects of CRU + WS on rice grain yield, N use efficiency and GHG emissions in multiple rice growing seasons. Relative to CF, rice grain yield from CF + WS decreased by 0.4–2.3% in 2012 and 2013 seasons but increased by 2.3–4.0% in 2014 and 2015 seasons, and significantly enhanced by 9.3% in 2016 season (p