Soil microbial species loss affects plant biomass and survival of an introduced bacterial strain, but not inducible plant defences

Viola Kurm*, Wim H. van der Putten, Ana Pineda, G.W.H. Hol

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

6 Citations (Scopus)


Background and Aims: Plant growth-promoting rhizobacteria (PGPR) strains can influence plant-insect interactions. However, little is known about the effect of changes in the soil bacterial community in general and especially the loss of rare soil microbes on these interactions. Here, the influence of rare soil microbe reduction on induced systemic resistance (ISR) in a wild ecotype of Arabidopsis thaliana against the aphid Myzus persicae was investigated. Methods: To create a gradient of microbial abundances, soil was inoculated with a serial dilution of a microbial community and responses of Arabidopsis plants that originated from the same site as the soil microbes were tested. Plant biomass, transcription of genes involved in plant defences, and insect performance were measured. In addition, the effects of the PGPR strain Pseudomonas fluorescens SS101 on plant and insect performance were tested under the influence of the various soil dilution treatments. Key Results: Plant biomass showed a hump-shaped relationship with soil microbial community dilution, independent of aphid or Pseudomonas treatments. Both aphid infestation and inoculation with Pseudomonas reduced plant biomass, and led to downregulation of PR1 (salicylic acid-responsive gene) and CYP79B3 (involved in synthesis of glucosinolates). Aphid performance and gene transcription were unaffected by soil dilution. Conclusions: Neither the loss of rare microbial species, as caused by soil dilution, nor Pseudomonas affect the resistance of A. Thaliana against M. persicae. However, both Pseudomonas survival and plant biomass respond to rare species loss. Thus, loss of rare soil microbial species can have a significant impact on both above- and belowground organisms.
Original languageEnglish
Pages (from-to)311-319
JournalAnnals of Botany
Issue number2
Publication statusPublished - 12 Feb 2018


  • Arabidopsis thaliana
  • induced systemic resistance
  • low-abundance soil microbes
  • Myzus persicae
  • PGPR

Fingerprint Dive into the research topics of 'Soil microbial species loss affects plant biomass and survival of an introduced bacterial strain, but not inducible plant defences'. Together they form a unique fingerprint.

Cite this