Green high-yield and high-efficiency technology: a new path balancing yield and ecology

As a staple food for more than half of the global population, the high and stable yield of rice is directly related to food security. As the world’s largest rice producer, China has increased rice yield per unit through intensive fertilization and flood irrigation, but this model has also brought problems such as soil degradation, water pollution, and greenhouse gas emissions. How to ensure food supply while breaking through resource and environmental constraints?

Xusheng Meng and colleagues from Nanjing Agricultural University proposed a green, high-yield, and high-efficiency rice technology system in a review study, providing a solution to this problem. The related paper has been published in Frontiers of Agricultural Science and Engineering (DOI: 10.15302/J-FASE-2025636).

Currently, China’s rice production is facing the dilemma of “high input and low efficiency”. Data shows that China accounts for 20% of the global rice planting area but consumes 37% of the nitrogen fertilizer, with nitrogen use efficiency lower than the world average. Excessive nitrogen fertilizer enters the environment through farmland runoff, leaching, and volatilization, leading to soil acidification and compaction, and exacerbating lake eutrophication and air pollution. At the same time, traditional flooded cultivation makes paddy fields an important source of greenhouse gas emissions. China’s paddy fields emit 712 million tons of carbon dioxide equivalents annually, higher than other major rice-producing countries.

In response to these challenges, researchers proposed three innovative technical paths based on experimental data from multiple regions across the country. The first is to optimize nutrient management strategies, balancing the rice population structure through the fertilization method of “reducing basal-tillering fertilizer and increasing panicle fertilizer”. In traditional cultivation, farmers tend to apply a large amount of fertilizer at the seedling stage to promote tillering, but excessive tillering easily leads to an increase in ineffective panicles and the risk of lodging. The new strategy precisely adjusts the proportion of nitrogen fertilizer allocated in different growth stages, which can not only promote effective tillering but also improve the development quality of panicles and grains in the later stage. Experiments show that this can increase nitrogen use efficiency by 8.1%–21.3%.

The second is the “carbon-nitrogen synergy” technology for improving soil fertility. The study found that combining crushed straw returning with organic fertilizer replacing part of chemical fertilizer can significantly increase soil organic carbon content and enhance the soil’s ability to retain water and nutrients. Long-term experiments show that this model can reduce ammonia volatilization loss by more than 17%, while activating the activity of functional microorganisms such as nitrogen-fixing bacteria and phosphate-solubilizing bacteria, and promoting nutrient conversion efficiency.

The third is the integrated water management technology of “water-saving and controlled drainage”. Different from the traditional full-period flooding, the “alternate wetting and drying” irrigation mode improves soil aeration, promotes root development, and reduces methane emissions by properly drying the fields in the late tillering stage. Demonstrations in the double-cropping rice areas of South China show that this technology can save 19% of water compared with conventional irrigation, reduce methane emissions by 16.2%, and keep the yield stable.

Researchers also proposed differentiated technical schemes according to the regional characteristics of China’s five major rice-growing regions. For example, in the Northeast region, nitrogen-zinc synergistic fertilization technology is used to solve the problem of seedling stunting caused by low temperature in early spring; in the mountainous areas of Southwest China, technologies such as sparse planting for strong plants and deep application of organic fertilizer are promoted to cope with topographical constraints; in the arid regions of Northwest China, film mulching hole sowing combined with controlled-release fertilizer is adopted to achieve water-saving and high yield. These technology combinations have achieved comprehensive benefits of increasing yield per mu by 6.3%–15.7% in different regions in demonstrations in Jiangsu, Northeast China, South China, etc.

The implementation of technology is inseparable from policy support and farmers’ participation. Through the “Science and Technology Courtyard” model, researchers have transformed complex technical parameters into simple operation standards such as the “three-looking fertilization method” (looking at seedling condition, soil, and weather), accelerating the large-scale application of green technologies. In the future, with the promotion of these technologies, it is expected to improve the nitrogen use efficiency of rice in China, reduce greenhouse gas emissions from paddy fields, and contribute to ensuring food security and sustainable agricultural development.