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Optimizing tillage and seeding strategies is important for increasing crop productivity and nitrogen use efficiency (NUE) while reducing environmental impact. A newly developed innovative no-till seeding (INtS) technology was shown to effectively enhance seeding quality and increase wheat yield in wet clay soil after puddled rice harvest in the Yangtze River Basin (YRB) of China. However, comprehensive assessments of the yield, NUE, and eco-environmental benefits of INtS technology have not been performed. The present study conducted a consecutive three-year field experiment combining field plots and microplots with the 15N tracer method using two wheat seeding technologies (INtS and typical rotary-till seeding (TRtS) technology) and three nitrogen (N) application rates (0, 90, and 180 kg ha−1). The study evaluated the yield, NUE, fate of fertilizer/straw N, N budgets, and environmental footprints of wheat production after rice harvesting. The results showed that compared with TRtS, the average yield, N uptake and NUE of wheat under INtS technology increased by 27.2%, 28.9%, and 31.9%, respectively. By tracing the multi-seasonal fate of 15N-labeled fertilizer/straw N in soil-crop systems, it was found that 43.8% and 6.0% of fertilizer N and rice straw N applied in the first wheat growing season were recovered by wheat plants in the same season under INtS technology, which significantly decreased to 29.0% and 4.1% for TRtS technology. Over the five growing seasons, the cumulative recoveries of fertilizer and straw N for INtS technology were 26.2% and 15.6% higher, while the total fertilizer and straw N losses were 20.6% and 20.0% lower than those for TRtS technology, respectively. Over 50% of straw N remained in the soil after the fifth growing season, while only 14.5–23.6% of fertilizer N remained. In addition, INtS technology significantly reduced the fertilizer/straw N losses when applied in the subsequent rice growing season. Unlike TRtS technology, INtS could maintain a low-level soil N balance (2.1 kg N ha−1 for N180) and generate less soil surface N surplus in the wheat growing season. On average, INtS significantly reduced the carbon footprint and N footprint in the wheat growing season by 26.8% and 19.1%, respectively. In conclusion, INtS technology can significantly improve crop production and agricultural sustainability while minimizing negative environmental impacts for wheat production after rice cultivation in the YRB of China and other areas of the world with similar field conditions. [Display omitted] • Innovative no-till seeding (INtS) technology increased grain yield by 27.2% and N uptake by 28.9%. • INtS technology showed higher fertilizer/straw N use efficiency and lower fertilizer/straw N losses. • INtS technology could maintain a low-level soil N balance and soil surface N surplus. • INtS technology reduced the carbon footprint and N footprint by 26.8% and 19.1%, respectively. • Higher productivity and N use efficiency while reducing environmental pressure can be achieved by INtS technology. [ABSTRACT FROM AUTHOR]

• N deficiency significantly affected GY and N utilization-related traits. • SDCs showed advantages over NSCs in GY, DM accumulation, and NUtE under N deficiency. • High-yielding SDCs is associated with the low GPC and high NUtE. Synthetic hexaploid wheat-derived cultivars (SDCs) show substantially improved yield potential compared with that of nonsynthetic-derived cultivars (NSCs) developed by conventional breeding. However, the relationship between the high-yielding traits of SDCs and nitrogen (N) use efficiency, especially their performance under N deficiency, is unclear. A field experiment was conducted in two successive seasons examining the responses of six genotypes (three SDCs and three NSCs) under two N treatments: N+ (N sufficiency, N nutrition index ≥ 1) and N− (N deficiency, N nutrition index < 1). N deficiency had a significantly negative effect on grain yield (GY) and yield-related traits. Compared with that of NSCs, SDCs showed 14% (N+) and 16% (N−) higher GY. This yield gain was mainly attributable to the higher total dry matter (DM) and post-anthesis DM accumulation of SDCs under both N treatments. On average, SDCs showed higher chlorophyll content than NSCs in the three upper leaves from 0 to 32 days post-anthesis, which was highly positively correlated with GY under both N treatments. Total and fertilizer N accumulation were significantly decreased under N deficiency. Compared with that of NSCs, SDCs showed lower grain protein concentrations under both N treatments, which was negatively correlated with GY. In addition, SDCs showed significantly higher N use efficiency and N utilization efficiency (NUtE) than NSCs, and a positive correlation was detected between NUtE and GY. The results indicated that SDCs show advantages over NSCs in GY, DM accumulation, and NUtE under N deficiency, and thus cultivation of SDCs shows potential to reduce N waste and environmental contamination. [ABSTRACT FROM AUTHOR]