Microorganisms in the phyllosphere of Norway spruce controlling nitrous oxide dynamics

Paul, Dhiraj; Paasisalo, Inga; Putkinen, Anuliina; Jones, Christopher M.; Kohl, Lukas; Hallin, Sara; Pihlatie, Mari; Siljanen, Henri M. P.

doi:10.1093/ismeco/ycaf196

Abstract

Current climate change assessments and greenhouse gas flux models often lack information on the microbiological processes that consume atmospheric nitrous oxide (N2O), a potent greenhouse gas. There is limited understanding of phyllospheric microorganisms controlling N2O exchange. In this study, we determined the microbial potential for N2O consumption in aboveground vegetation in boreal forests. For this, we collected shoot samples from upland spruce forests in Finland and used a novel targeted metagenomics approach with a hybridization capture of gene-specific probes. Most of the samples contained nosZ genes, encoding the N2O reductase. Phylogenetic placement showed a significantly higher relative abundance (P < .01) of nosZ Clade I than nosZ Clade II. Bacterial members such as Comamonadaceae, Hydrogenophaga, and Paracoccus, which all harbor nosZ Clade I, were found in high relative abundance in the spruce shoots across the sites, suggesting they play a role in N2O consumption capabilities in the spruce phyllosphere. Anoxic incubations, utilizing gas chromatography for N2O analyses, showed potential N2O consumption activity across the spruce samples. The presence of nirK and nirS suggests potential for denitrification, possibly resulting in N2O production. Our finding provides evidence of microbial communities in spruce canopies with potential for N2O exchange. Given the vast coverage of boreal forests globally, understanding the role of phyllospheric microorganisms in N2O exchange is crucial for improving the accuracy of greenhouse gas models and enhancing climate prediction reliability.

Keywords

greenhouse gas (GHG); nitrous oxide; nosZ; phyllospheric; microbial community; probe captured metagenomics

Published in

ISME Communications
2025, volume: 5, number: 1, article number: ycaf196
Publisher: OXFORD UNIV PRESS

SLU Authors

Jones, Christopher
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
Hallin, Sara
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences

UKÄ Subject classification

Microbiology
Ecology

Publication identifier

DOI: https://doi.org/10.1093/ismeco/ycaf196

Permanent link to this page (URI)

https://res.slu.se/id/publ/144997