Assembly of root-associated N₂O-reducing communities of annual crops is governed by selection for nosZ Glade I over Glade II

Sammanfattning

The rhizosphere is a hotspot for denitrification. The nitrous oxide (N₂O) reductase among denitrifiers and nondenitrifying N₂O reducers is the only known N₂O sink in the biosphere. We hypothesized that the composition of root-associated N₂O-reducing communities when establishing on annual crops depend on soil type and plant species, but that assembly processes are independent of these factors and differ between nosZ clades I and II. Using a pot experiment with barley and sunflower and two soils, we analyzed the abundance, composition, and diversity of soil and root-associated N₂O reducing communities by qPCR and amplicon sequencing of nosZ. Clade I was more abundant on roots compared to soil, while clade II showed the opposite. In barley, this pattern coincided with N₂O availability, determined as potential N₂O production rates, but for sunflower no N₂O production was detected in the root compartment. Root and soil nosZ communities differed in composition and phylogeny-based community analyses indicated that assembly of root-associated N₂O reducers was driven by the interaction between plant and soil type, with inferred competition being more influential than habitat selection. Selection between clades I and II in the root/soil interface is suggested, which may have functional consequences since most clade I microorganisms can produce N₂O.

Nyckelord

denitrification; nitrous oxide; rhizosphere; soil

Publicerad i

FEMS Microbiology Ecology
2022, volym: 98, nummer: 9
Utgivare: OXFORD UNIV PRESS

SLU författare

• Graf, Daniel

  • Institutionen för skoglig mykologi och växtpatologi, Sveriges lantbruksuniversitet
    

• Jones, Christopher

  • Institutionen för skoglig mykologi och växtpatologi, Sveriges lantbruksuniversitet
    

• Zhao, Enid Ming

  • Institutionen för växtbiologi, Sveriges lantbruksuniversitet
    

• Hallin, Sara

  • Institutionen för skoglig mykologi och växtpatologi, Sveriges lantbruksuniversitet
    

UKÄ forskningsämne

Mikrobiologi

Publikationens identifierare

• DOI: https://doi.org/10.1093/femsec/fiac092

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/118790