This study presents detailed crop and gas flux data from two years of rice production at the experimental farm of the ICAR-Indian Agricultural Research Institute, New Delhi, India. In comparing 4 nitrogen (N) fertiliser regimes across 4 rice cultivars (CRD 310, IR-64, MTU 1010, P-44), we have added to growing evidence of the environmental costs of rice production in the region. The study shows that rice cultivar can impact yields of both grain, and total biomass produced in given circumstances, with the CRD 310 cultivar showing consistently high nitrogen use efficiency (NUE) for total biomass compared with other tested varieties, but not necessarily with the highest grain yield, which was P-44 in this experiment. While NUE of the rice did vary depending on experimental treatments (ranging from 41% to 73%), 73%), this did not translate directly into the reduction of emissions of ammonia (NH₃) and nitrous oxide (N₂O). Emissions were relatively similar across the different rice cultivars regardless of NUE. Conversely, agronomic practices that reduced total N losses were associated with higher yield. In terms of fertiliser application, the outstanding impact was of the very high methane (CH₄) emissions as a result of incorporating farmyard manure (FYM) into rice paddies, which dominated the overall effect on global warming potential. While the use of nitrification and urease inhibiting substances decreased N₂O emissions overall, NH₃ emissions were relatively unaffected (or slightly higher). Overall, the greatest reduction in greenhouse gas (GHG) emissions came from reducing irrigation water added to the fields, resulting in higher N₂O, but significantly less CH₄ emissions, reducing net GHG emission compared with continuous flooding. Overall, genetic differences generated more variation in yield and NUE than agronomic management (excluding controls), whereas agronomy generated larger differences than genetics concerning gaseous losses. This study suggests that a mixed approach needs to be applied when attempting to reduce pollution and global warming potential from rice production and potential pollution swapping and synergies need to be considered. Finding the right balance of rice cultivar, irrigation technique and fertiliser type could significantly reduce emissions, while getting it wrong can result in considerably poorer yields and higher pollution.

本研究提供了印度新德里 ICAR-印度农业研究所实验农场两年水稻生产的详细作物和气体通量数据。在比较 4 个水稻品种（CRD 310、IR-64、MTU 1010、P-44）的 4 种氮 (N) 施肥方案时，我们增加了该地区水稻生产的环境成本的越来越多的证据。该研究表明，在特定情况下，水稻品种会影响谷物的产量和总生物量，与其他测试品种相比，CRD 310 品种的总生物量显示出始终如一的高氮利用效率 (NUE)，但不一定是最高的谷物产量，在本实验中为 P-44。虽然水稻的 NUE 确实因实验处理而异（从 41% 到 73%），73%），₃ )和一氧化二氮(N ₂ O)。无论 NUE 是多少，不同水稻品种的排放量都相对相似。相反，减少总氮损失的农艺措施与更高的产量相关。在施肥方面，突出的影响是在稻田中施用农家肥（FYM）导致甲烷（ CH _{4 ）排放量非常高，这在全球变暖潜能值的总体影响中占主导地位。}虽然硝化作用和脲酶抑制物质的使用减少了 N ₂ O 的总体排放量，但 NH ₃排放量相对未受影响（或略高）。_{总体而言，温室气体 (GHG) 排放量的最大减少来自减少田间灌溉用水，导致 N 2} O增加，但 CH _{4显着减少}排放，与持续洪水相比减少了温室气体净排放量。总体而言，遗传差异比农艺管理（不包括对照）在产量和 NUE 方面产生更多变化，而农学在气体损失方面比遗传学产生更大的差异。这项研究表明，在尝试减少水稻生产造成的污染和全球变暖的可能性时，需要采用混合方法，并且需要考虑潜在的污染交换和协同作用。找到水稻品种、灌溉技术和肥料类型的正确平衡可以显着减少排放，而错误的平衡会导致产量大幅下降和污染加剧。