Effects of Nitrogen Fertilizer Management Strategies on Post-Anthesis Photosynthetic Characteristics, Nitrogen Transport and Soil Nitrogen Properties in Winter Wheat

To investigate the effects of different nitrogen fertilizer management strategies on post-anthesis photosynthetic characteristics, nitrogen translocation, and yield formation of winter wheat, this study was based on a long-term fixed-site experiment established in 2013. Four treatments were set up: no nitrogen application (CK), conventional nitrogen application (FP), optimized nitrogen application (OPT), and controlled-release nitrogen fertilizer (CRF), to study their effects on the post-anthesis photosynthesis, nitrogen translocation, yield, and soil characteristics of winter wheat. Nitrogen application significantly increased flag leaf SPAD value, green leaf area index, net photosynthetic rate, and yield components ( p< 0.05). The OPT treatment achieved the highest yield of 8871.69 kg·hm−2, which was 2.32% and 4.00% higher than that of FP and CRF, respectively, and its nitrogen use efficiency indicators were also relatively high. Nitrogen application increased urease activity and altered microbial community composition. OPT could maintain a relatively high post-anthesis photosynthetic capacity and promote efficient nitrogen utilization, suggesting that it a suitable fertilization mode for high-yield and high-efficiency winter wheat production.