Life-Cycle Assessment of Greenhouse Gas Reduction Potential of BNI-Enabled Wheat

― Wheat with 40% nitrification inhibition rate will lead to a 9.5% reduction in GHG emissions from wheat production worldwide ―

JIRCAS, in collaboration with the International Maize and Wheat Improvement Center (CIMMYT), has developed a new model based on life-cycle assessment (LCA) to evaluate the total greenhouse gas (GHG) emissions generated at each stage of wheat production for biological nitrification inhibition (BNI)-enabled wheat, which shows high productivity with low nitrogen fertilizer. 

The nitrification inhibition rate of soil for BNI-enabled wheat, which was announced in a press release on August 31, 2021, is about 30% in actual measurement. However, the research group has been developing a feasible target of 40% nitrification inhibition rate in order to achieve carbon neutrality by 2050. 

In this study, we applied a new model based on LCA with corrections for BNI, and showed that the life-cycle GHG emissions can be reduced by 15.9% when BNI-enabled wheat with 40% nitrification inhibition rate is applied. We also estimated that the nitrogen use efficiency of wheat in this case would be improved by 16.7%, and the amount of fertilizer nitrogen applied could be reduced by 15.0%.　

On the other hand, BNI-enabled wheat has been shown to exhibit good nitrification inhibition in slightly acidic to neutral soils (pH 5.5-7.0). About 30% (about 72 million ha) of the world's wheat production area (about 240 million ha) meets these conditions, and it was estimated that a 9.5% reduction in nitrogen fertilizer-derived greenhouse gases would be possible if BNI-enabled wheat with 40% nitrification inhibition were introduced.

The development of BNI-enabled wheat will contribute to the establishment of an agricultural system that combines high productivity with reduced environmental impact from agriculture, and is expected to have an effect on mitigating global warming.

The results of this research have been published in the online edition of the scientific journal Environmental Science and Pollution Research (September 1, 2021 Japan time).

Authors

A Leon, GV Subbarao, M Kishii, N Matsumoto and K Gideon 

Title

An ex ante life cycle assessment of wheat with high biological nitrification inhibition capacity

Journal

Environmental Science and Pollution Research 
DOI: https://doi.org/10.1007/s11356-021-16132-2

JIRCAS President :　KOYAMA Osamu
Program Director :     HAYASHI Keiichi  
Researcher-in-charge : LEON Ai (Social Sciences Division)　　　　
　　　　　　SUBBARAO Guntur (Crop, Livestock and Environment Division)
　　　　　　MATSUMOTO Naruo (Crop, Livestock and Environment Division)
Press Coordinator : OMORI Keisuke (Head, Information and Public Relations Office)
E-mail : koho-jircas@ml.affrc.go.jp