Host Genotype and Nitrogen Form Shape the Root Microbiome of Pinus radiata

Abstract

A central challenge in community ecology is understanding the role that phenotypic variation among genotypes plays in structuring host-associated communities. While recent studies have investigated the relationship between plant genotype and the composition of soil microbial communities, the effect of genotype-by-environment interactions on the plant microbiome remains unclear. In this study, we assessed the influence of tree genetics (G), nitrogen (N) form and genotype-by-environment interaction (G x N) on the composition of the root microbiome. Rhizosphere communities (bacteria and fungi) and root-associated fungi (including ectomycorrhizal and saprotrophic guilds) were characterised in two genotypes of Pinus radiata with contrasting physiological responses to exogenous organic or inorganic N supply. Genotype-specific responses to N form influenced the composition of the root microbiome. Specifically, (1) diversity and composition of rhizosphere bacterial and root-associated fungal communities differed between genotypes that had distinct responses to N form, (2) shifts in the relative abundance of individual taxa were driven by the main effects of N form or host genotype and (3) the root microbiome of the P. radiata genotype with the most divergent growth responses to organic and inorganic N was most sensitive to differences in N form. Our results show that intraspecific variation in tree response to N form has significant consequences for the root microbiome of P. radiata, demonstrating the importance of genotype-by-environment interactions in shaping host-associated communities.

Keywords

Root microbiome; Genotype-by-environment interaction; Nitrogen form; Host genotype; Intraspecific variation; Root-associated fungi

Published in

Microbial Ecology
2018, Volume: 75, number: 2, pages: 419-433 Publisher: SPRINGER

SLU Authors

• Love, Jonathan

  • Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences
    
  • University of Canterbury

UKÄ Subject classification

Ecology


Publication identifier

DOI: https://doi.org/10.1007/s00248-017-1055-2

Permanent link to this page (URI)

https://res.slu.se/id/publ/93374