Irrigated transplanted flooded rice is a major source of methane (CH₄) emission. We carried out experiments for 2 years in irrigated flooded rice to study if interventions like methane-utilizing bacteria, Blue-green algae (BGA), and Azolla could mitigate the emission of CH₄ and nitrous oxide (N₂O) and lower the yield-scaled global warming potential (GWP). The experiment included nine treatments: T₁ (120 kg N ha⁻¹ urea), T₂ (90 kg N ha⁻¹ urea + 30 kg N ha⁻¹ fresh Azolla), T₃ (90 kg N ha⁻¹ urea + 30 kg N ha⁻¹ Blue-green algae (BGA), T₄ (60 kg N ha⁻¹ urea + 30 kg N ha⁻¹ BGA + 30 kg N ha⁻¹ Azolla, T₅ (120 kg N ha⁻¹ urea + Hyphomicrobium facile MaAL69), T₆ (120 kg N ha⁻¹ by urea + Burkholderia vietnamiensis AAAr40), T₇ (120 kg N ha⁻¹ by urea + Methylobacteruim oryzae MNL7), T₈ (120 kg N ha⁻¹ urea + combination of Burkholderia AAAr40, Hyphomicrobium facile MaAL69, Methylobacteruim oryzae MNL7), and T₉ (no N fertilizer). Maximum decrease in cumulative CH₄ emission was observed with the application of Methylobacteruim oryzae MNL7 in T₇ (19.9%), followed by Azolla + BGA in T₄ (13.2%) as compared to T₁ control. N₂O emissions were not significantly affected by the application of CH₄-oxidizing bacteria. However, significantly lower (P<0.01) cumulative N₂O emissions was observed in T₄ (40.7%) among the fertilized treatments. Highest yields were observed in Azolla treatment T₂ with 25% less urea N application. The reduction in yield-scaled GWP was at par in T₄ (Azolla and BGA) and T₇ (Methylobacteruim oryzae MNL7) treatments and reduced by 27.4% and 15.2% in T₄ and T₇, respectively, as compared to the T₁ (control). K-means clustering analysis showed that the application of Methylobacteruim oryzae MNL7, Azolla, and Azolla + BGA can be an effective mitigation option to reduce the global warming potential while increasing the yield.

灌溉移栽淹水水稻是甲烷 (CH ₄ ) 排放的主要来源。我们在灌溉水淹水稻中进行了为期 2 年的实验，以研究诸如利用甲烷的细菌、蓝绿藻 (BGA) 和Azolla等干预措施是否可以减少 CH ₄和一氧化二氮 (N ₂ O)的排放并降低产量- 全球变暖潜能值 (GWP)。实验包括九个处理：T ₁ (120 kg N ha ^-1尿素)、T ₂ (90 kg N ha ^-1尿素 + 30 kg N ha ^-1新鲜红萍)、T ₃ (90 kg N ha ^-1尿素 + 30 公斤 N 公顷^-1蓝绿藻 (BGA), T ₄ (60 kg N ha ^-1尿素 + 30 kg N ha ^-1 BGA + 30 kg N ha ^-1 Azolla , T ₅ (120 kg N ha ^-1尿素 + Hyphomicrobium facile MaAL69) , T ₆ (120 kg N ha ^-1尿素 + Burkholderia vietnamiensis AAAr40), T ₇ (120 kg N ha ^-1尿素 + Methylobacteruim oryzae MNL7), T ₈ (120 kg N ha ^-1尿素 + Burkholderia AAAr40 的组合, Hyphomicrobium facial MaAL69,Methylobacteruim oryzae MNL7) 和 T ₉（无氮肥）。与T ₁对照相比，在T _{7 中}应用米氏甲基杆菌MNL7 (19.9%)，然后在T _{4 中应用}Azolla + BGA (13.2%)观察到累积CH ₄排放的最大减少。N ₂ O 排放不受CH ₄氧化细菌的应用的显着影响。然而，在施肥处理的T ₄ (40.7%) 中观察到显着较低( P <0.01) 累积N ₂ O 排放。在Azolla中观察到最高产量处理T ₂尿素氮施用量减少25%。在产率缩放的GWP的减少是按面值T中₄（满江红和BGA）和T ₇（Methylobacteruim曲霉MNL7）治疗和27.4％和15.2％T中减少₄和T ₇分别相比到T ₁（控制）。K-means聚类分析表明，应用Methylobacteruim oryzae MNL7、Azolla和Azolla + BGA 可以成为降低全球变暖潜势同时提高产量的有效缓解方案。