As one of the world’s most important food crops, wheat not only provides calories and nutrition for billions of people but also plays a core role in China’s food security strategy. In recent years, China has significantly increased wheat yields through agronomic innovation and technological advancements. However, issues such as excessive fertilizer application and soil degradation in traditional production have not only increased carbon emissions but also hindered sustainable agricultural development. How can we ensure high yields while improving nitrogen use efficiency and reducing environmental impact? This question has become a significant topic in agricultural science.
Recently, Associate Professor Xinglong Dai from Agronomy College of Shandong Agricultural University and his colleagues proposed a quantitative design theory and technical pathway for green yield increase and efficient nitrogen utilization in winter wheat, providing new insights to address this challenge. Related paper has been published in Frontiers of Agricultural Science and Engineering (DOI: 10.15302/J-FASE-2025631).
Based on the development history of wheat production in China, Academician Songlie Yu from Shandong Agricultural University proposed the “Three-Stage Theory”: First, the breakthrough from low yield to medium yield primarily relies on improving soil fertility; second, the key to transitioning from medium yield to high yield is coordinating the development of the population and individuals; third, to achieve super high yield from high yield, it is necessary to resolve internal contradictions such as the source-sink relationship and carbon-nitrogen metabolism balance. Currently, the core bottlenecks limiting green yield increase in winter wheat are: an imbalance in competition between population and individuals leading to decreased resource utilization; insufficient dry matter accumulation after flowering affecting grain filling; and the degradation of soil physical and chemical properties limiting root growth.
To overcome these bottlenecks, the researchers constructed an optimization framework for the “soil-crop system” and proposed several quantifiable technical indicators. In terms of population structure, they recommended a planting density of 330–375 plants m^–2 for large panicle varieties and 225–270 plants m^–2 for medium panicle varieties, ensuring effective ear numbers while avoiding excessive individual competition. For soil improvement, they adopted a “straw return + rotary tillage and deep tillage rotation” model: after two consecutive years of rotary tillage, one deep tillage can reduce soil bulk density at 0–20 cm depth and increase organic matter content to over 20 g·kg⁻¹, while also reducing the carbon footprint by 1.87 tons of CO₂ equivalent per hectare.
In terms of planting methods, wide-row strip sowing technology (with a sowing band width of 6–8 cm) effectively alleviates plant competition issues associated with traditional narrow-row sowing. By increasing row spacing, the root distribution of the wheat becomes more uniform, significantly increasing nitrogen absorption from deep soil layers, with light interception rates reaching over 90% during the grain filling period. Coupled with moderately delayed sowing, this approach not only improves nitrogen use efficiency in grains but also enhances the lodging resistance of the stems, achieving the dual goals of “no yield reduction and higher efficiency”.
The “comprehensive management of the soil-crop system” model is not merely an aggregation of individual measures; it achieves precise matching of resource input and output through the regulation of population structure, soil health, and root-crown interactions. This model has shown significant effects in the Huang-Huai-Hai wheat region: compared to conventional farmer management, it has resulted in a 22.5% increase in winter wheat yield, a 49.2% improvement in nitrogen use efficiency, and a reduction in the residue of inorganic nitrogen and greenhouse gas emissions in the soil.
This research closely integrates theoretical innovation with practical production. Through clear quantifiable indicators, farmers can adjust management practices based on actual conditions, avoiding a one-size-fits-all approach. Future efforts should further explore the applicability of this technical system in different ecological regions and quantify the carbon footprint and economic benefits throughout the entire life cycle, providing support for the green transformation of agriculture in China.
DOI: 10.15302/J-FASE-2025631