Reduced methane emissions in transgenic rice genotypes are associated with altered rhizosphere microbial hydrogen cycling
- Ling-Dong Shi
- Maria Florencia Ercoli
- Junhyeong Kim
- Artur Teixeira de Araujo Junior
- Katerina Estera-Molina
- Subah Soni
- Tracy Satomi Weitz
- Alexandra M. Shigenaga
- Ilija Dukovski
- Rohan Sachdeva
- Halbay Turumtay
- Katherine B. Louie
- Benjamin P. Bowen
- Suzanne M. Kosina
- Henrik V. Scheller
- Jennifer Pett-Ridge
- Daniel Segrè
- Trent R. Northen
- Pamela C. Ronald
- Jillian F. Banfield
2026-01-26
Rice paddies significantly contribute to atmospheric methane (CH 4 ). Here, we show that two independent rice genotypes overexpressing genes for PLANT PEPTIDES CONTAINING SULFATED TYROSINE ( PSY ) reduce cumulative CH 4 emissions by 38% (PSY1) and 58% (PSY2) over 70 days of growth compared with controls. Genome-resolved metatranscriptomic data from PSY rhizosphere soils reveal lower ratios of gene activities for (mostly hydrogenotrophic) CH 4 production versus consumption, decreased activity of H 2 -producing genes, and increased activity of bacterial H 2 oxidation pathways. Metabolic modeling using metagenomic and metabolomic data predicts elevated H 2 oxidation and suppressed H 2 production in the PSY rhizosphere. Assembled genomes of rhizosphere H 2 -oxidizing bacteria are enriched in genes utilizing gluconeogenic acids compared with H 2 -producing counterparts, and their activities are likely stimulated by elevated levels of gluconeogenic acids, primarily amino acids, in PSY root exudates. Overall, our study indicates that decreased CH 4 emissions are due to a lower amount of H 2 available for hydrogenotrophic methanogenesis and provides a powerful strategy to mitigate CH 4 emissions from increasingly widespread rice cultivation.