Critical perspectives on the use of methanotrophs in rice farming: Advances in microbial climate mitigation

The use of methanotrophs in rice fields is an innovative and promising tool in climate-smart rice production. We reviewed major databases for studies since 2015 on methanotrophs in rice farming, focusing on methane (CH 4 ) reduction, plant growth effects, implementation strategies, and feasibility. Multiple field and pot experiments show that methanotrophic inoculation can significantly cut CH4 emissions (reductions of about 12% up to 60%) and often improve rice growth and yields (by 10–35% or more), especially under reduced fertilizer use. Methanotrophs also help plant nutrition through nitrogen fixation and other growth-promoting traits, enabling higher yields with less chemical fertilizer. However, practical challenges remain. The effectiveness of methanotroph application varies with field conditions, and long-term establishment of introduced strains is uncertain. There are trade-offs, such as potential increases in nitrous oxide (N 2 O) emissions in certain circumstances, competition with native microbes, and economic and logistical hurdles in large-scale inoculant applications, which temper enthusiasm. We critically examine these limitations, including the need for repeated treatments and the feasibility of widespread use. Methanotroph-based solutions in rice paddies show clear potential for climate mitigation and sustainable farming, but success depends on overcoming practical deployment issues and avoiding adverse ecological effects. Ongoing research into better delivery methods, bacterial mixes, and field testing will be key to moving this approach from trials to routine agricultural practice.