Grain protein content (GPC) often increases with nitrogen (N) fertilizer; however, low GPC is preferred for soft wheat (Triticum aestivum L.). The combined effects of decreasing N and increasing seed rate (SR) on soft wheat quality, economic benefits (Eb), apparent N recovery (ARN), and soil nitrate-N residual (SNR) are poorly understood. Field experiments were conducted with three SRs (SR135, SR180, and SR225) and two N levels (N235 and N290) in 2017-2018, and three N levels (N290, N235, and N180) with a control (N0) in 2018-19. The results showed that storage proteins, GMP, HMW-GS, and Zeleny sedimentation value significantly decreased with lower N levels and increased with higher SR. At the same SR, the significant difference for the parameters mentioned were greater at a low N rate than at a high rate. Furthermore, grain yield (GY), Eb, ARN, and SNR were significantly affected by N and SR. Increasing SR from 135 to 180 resulted in an average Eb increase of 13.32%, while increasing from 180 to 225 led to a decline of 3.75%. Compared to N290, N235 decreased SNR and GPC by 27.5% and 4.7%, respectively, but increased ARN by 18.3%. The highest Eb (13,914 CNY) and ARN value (57.5%) were observed with the treatment (N235SR180). Additionally, optimal combination for maximizing GY (90%), Eb (87.8%), and ARN (97%) was found at N235SR198, according to regression and spatial analysis. This study confirmed that optimizing N and SR can improve soft wheat quality and resource use efficiency without decreasing yield.

来源平台：JOURNAL OF CEREAL SCIENCE