Japan International Research Center for Agricultural Sciences, Ohwashi, Tsukuba, Ibaraki, 305-8686, Japan.
International Maize and Wheat Improvement Center, Carretera Mexico-Veracruz Km.45 El Batán, Texcoco, C.P, 56237, Mexico.
Environ Sci Pollut Res Int. 2022 Jan;29(5):7153-7169. doi: 10.1007/s11356-021-16132-2. Epub 2021 Sep 1.
It is essential to increase food production to meet the projected population increase while reducing environmental loads. Biological nitrification inhibition (BNI)-enabled wheat genetic stocks are under development through chromosome engineering by transferring chromosomal regions carrying the BNI trait from a wild relative (Leymus racemosus (Lam.) Tzvelev) into elite wheat varieties; field evaluation of these newly developed BNI-wheat varieties has started. Ten years from now, BNI-enabled elite wheat varieties are expected to be deployed in wheat production systems. This study aims to evaluate the impacts of introducing these novel genetic solutions on life cycle greenhouse gas (LC-GHG) emissions, nitrogen (N) fertilizer application rates and N-use efficiency (NUE). Scenarios were developed based on evidence of nitrification inhibition and nitrous oxide (NO) emission reduction by BNI crops and by synthetic nitrification inhibitors (SNIs), as both BNI-wheat and SNIs slow the nitrification process. Scenarios including BNI-wheat will inhibit nitrification by 30% by 2030 and 40% by 2050. It was assumed that N fertilizer application rates can potentially be reduced, as N losses through NO emissions, leaching and runoff are expected to be lower. The results show that the impacts from BNI-wheat with 40% nitrification inhibition by 2050 are assessed to be positive: a 15.0% reduction in N fertilization, a 15.9% reduction in LC-GHG emissions, and a 16.7% improvement in NUE at the farm level. An increase in ammonia volatilization had little influence on the reduction in LC-GHG emissions. The GHG emissions associated with N fertilizer production and soil NO emissions can be reduced between 7.3 and 9.5% across the wheat-harvested area worldwide by BNI-wheat with 30% and 40% nitrification inhibition, respectively. However, the present study recommends further technological developments (e.g. further developments in BNI-wheat and the development of more powerful SNIs) to reduce environmental impacts while improving wheat production to meet the increasing worldwide demand.
为了应对预计的人口增长，同时减少环境负荷，增加粮食产量至关重要。目前正在通过染色体工程开发具有生物硝化抑制（BNI）功能的小麦遗传资源，即将携带 BNI 特性的染色体区域从野生近缘种（长穗偃麦草（Lam.）Tzvelev）转移到优良小麦品种中；这些新开发的 BNI-小麦品种的田间评价已经开始。从现在起十年后，预计具有 BNI 功能的优良小麦品种将在小麦生产系统中得到应用。本研究旨在评估引入这些新型遗传解决方案对生命周期温室气体（LC-GHG）排放、氮肥施用量和氮利用效率（NUE）的影响。基于 BNI 作物和合成硝化抑制剂（SNI）对硝化抑制和一氧化二氮（NO）排放减少的证据，开发了不同的情景，因为 BNI 小麦和 SNI 都能减缓硝化过程。到 2030 年，包含 BNI 小麦的情景将使硝化作用抑制 30%，到 2050 年抑制 40%。假设氮肥施用量可能会减少，因为预计通过 NO 排放、淋溶和径流损失的氮会减少。结果表明，到 2050 年，硝化作用抑制 40%的 BNI 小麦的影响被评估为积极的：氮肥用量减少 15.0%，LC-GHG 排放减少 15.9%，农场层面氮利用效率提高 16.7%。氨挥发增加对 LC-GHG 排放减少的影响较小。通过 BNI 小麦使硝化作用分别抑制 30%和 40%，可使全球小麦种植区的与氮肥生产和土壤 NO 排放相关的温室气体排放分别减少 7.3%和 9.5%。然而，本研究建议进一步开发技术（例如进一步开发 BNI 小麦和开发更有效的 SNI），在提高小麦产量以满足全球不断增长的需求的同时，减少环境影响。
