Plant roots affect free-living diazotroph communities in temperate grassland soils despite decades of fertilization

Marlies Dietrich, Christopher Panhölzl, Roey Angel, Andrew T Giguere, Dania Randi, Bela Hausmann, Craig W Herbold, Erich M Pötsch, Andreas Schaumberger, Stephanie A Eichorst, Dagmar Woebken (Corresponding author)

Publications: Contribution to journalArticlePeer Reviewed

Abstract

Fixation of atmospheric N2 by free-living diazotrophs accounts for an important proportion of nitrogen naturally introduced to temperate grasslands. The effect of plants or fertilization on the general microbial community has been extensively studied, yet an understanding of the potential combinatorial effects on the community structure and activity of free-living diazotrophs is lacking. In this study we provide a multilevel assessment of the single and interactive effects of different long-term fertilization treatments, plant species and vicinity to roots on the free-living diazotroph community in relation to the general microbial community in grassland soils. We sequenced the dinitrogenase reductase (nifH) and the 16S rRNA genes of bulk soil and root-associated compartments (rhizosphere soil, rhizoplane and root) of two grass species (Arrhenatherum elatius and Anthoxanthum odoratum) and two herb species (Galium album and Plantago lanceolata) growing in Austrian grassland soils treated with different fertilizers (N, P, NPK) since 1960. Overall, fertilization has the strongest effect on the diazotroph and general microbial community structure, however with vicinity to the root, the plant effect increases. Despite the long-term fertilization, plants strongly influence the diazotroph communities emphasizing the complexity of soil microbial communities' responses to changing nutrient conditions in temperate grasslands.

Original languageEnglish
Article number846
Number of pages14
JournalCommunications Biology
Volume7
Issue number1
DOIs
Publication statusPublished - 11 Jul 2024

Austrian Fields of Science 2012

  • 106026 Ecosystem research
  • 105904 Environmental research
  • 106022 Microbiology

Keywords

  • Plant Roots/microbiology
  • Grassland
  • Soil Microbiology
  • Fertilizers/analysis
  • Poaceae
  • Nitrogen Fixation
  • Soil/chemistry
  • RNA, Ribosomal, 16S/genetics
  • Oxidoreductases/genetics
  • Rhizosphere

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