The Innovation Team of Farming System and Agro-Ecology, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (ICS-CAAS), demonstrated the characteristics and biological mechanisms of high-yielding winter wheat varieties with less nitrous oxide (N2O) emissions based on the field experiments. This research has been published in Agriculture, Ecosystems and Environment recently, which is another important finding revealed by the team following high-yielding modern rice varieties with low methane emissions.

According to the team leader Dr. Zhang Weijian, food security is the primary goal of crop production, while Carbon Peak and Carbon Neutrality are also important parts which need to be considered in the current and future crop productions of China. Wheat is the second-largest staple food in China and wheat field is also a main emission source of N2O. Meanwhile, N2O is the third most important greenhouse gas (GHG). It is essential to find a synergistic approach to reduce N2O emissions while maintaining or increasing crop yield for achieving food security and GHG mitigation.

The study demonstrates that the morphological and physiological characteristics of wheat have changed greatly with the improvement of winter wheat varieties in China. Newly-released winter wheat varieties generally achieve high productivity and strong root absorption capacity. These characteristics could increase the utilization of soil nitrogen by plants and, consequently, decrease nitrogen availability for N2O emissions. Through multi-species comparison in the fields, this research also found that grain yield increased by 6.8% per decade, and nitrogen absorption of winter wheat increased simultaneously with the variety improvement. In addition, the cumulative and yield-scaled N2O emissions from the winter wheat field decreased by 2.0% and 8.9% per decade, respectively. N2O emissions negatively correlated with crop nitrogen absorption capacity. This research contributes significantly to build up basic knowledge for wheat cultivar selection and agronomic management innovation to achieve higher yield and reduce N2O emissions from winter wheat fields.

This work is first-authored by Dr. Chen Huan, who graduated from ICS-CAAS. Dr. Zhang Weijian and Dr. Cao Chengfu are co-corresponding authors. The research was supported by National Key Research and Development Program of the 13th Five-Year plan and the Science and Technology Innovation Project of CAAS.

Reference resource: https://www.sciencedirect.com/science/article/pii/S0167880921002619

By Zhang Weijian (zhangweijian@caas.cn)