How to balance high corn yields with resource efficiency?

As the most widely planted and highest-yielding grain crop in China, increasing corn yields is crucial for ensuring food security. However, with the growing global population and limited arable land, the challenge of enhancing corn production while reducing environmental burdens has become a core issue for sustainable agricultural development.

Recently, a team of researchers led by Professor Peng Hou from the Institute of Crop Sciences, Chinese Academy of Agricultural Sciences systematically summarized the limiting factors in corn production and proposed a green production scheme that balances high yield with efficient resource utilization based on quantitative design principles. The related paper has been published in Frontiers of Agricultural Science and Engineering (DOI: 10.15302/J-FASE-2025601).

Currently, the increase in corn yield in China faces multiple constraints. In terms of climate, reduced solar radiation and extreme weather events (such as droughts and floods) directly affect photosynthesis and nutrient accumulation. From a soil perspective, long-term shallow tillage has led to compaction of the plow layer, resulting in a yield reduction of approximately 4.8% to 20.2%. Management issues, such as low planting density and improper fertilization, are also prevalent—for instance, the planting density of corn in China is significantly lower than in the USA, and in some areas, excessive fertilization not only reduces nutrient utilization but also leads to soil degradation and groundwater pollution. These factors collectively hinder the full potential of corn yields, highlighting resource waste and environmental pressure.

To address these issues, the researchers proposed three optimization strategies based on quantitative design principles. First is the matching of planting density with solar radiation. By analyzing the differences in solar radiation across various regions in China, areas with abundant sunlight, such as the Northwest, can achieve high yields by increasing planting density, while eastern regions should adjust planting density according to radiation levels to avoid resource waste. Second is the matching of varieties with population structure, recommending the selection of compact varieties: these corn plants have smaller leaf angles, which can reduce shading and allow more light to reach the middle and lower leaves, leading to higher light energy utilization compared to sprawling varieties. Third is the functional matching of tillage, root systems, and canopy, which involves deep loosening of the soil to break the plow layer, optimizing root distribution, and using drip irrigation and fertilization techniques to provide precise water and nutrients, achieving a synergistic efficiency between underground absorption and above-ground growth.

Based on existing research data, after implementing the quantitative design scheme, corn yields in the Southwest, Huang-Huai-Hai, North China, and Northwest regions increased by 10.5%, 2.7%, 5.2%, and 10.3%, respectively, without increasing nitrogen fertilizer input. Notably, the drip irrigation and fertilization technology has shown remarkable results in the arid Northwest, significantly enhancing yields compared to traditional cultivation, with average improvements in water and nutrient utilization rates exceeding 30%. This technology has now been promoted across 4 million hectares of corn fields in China, accounting for approximately 9% of the total area, particularly effective in arid and semi-arid regions such as the Northwest and Northeast.

Through quantitative design, not only can the consumption of fertilizers and water resources be reduced, but greenhouse gas emissions can also be lowered. The study suggests that future efforts should further integrate regional climate characteristics to promote personalized schemes—such as optimizing density and light matching in the Southwest and strengthening the breeding of stress-resistant varieties in the Huang-Huai-Hai region.