Journal Article

Rhizodeposition shapes rhizosphere microbial community structure in organic soil

Telfer, Gillian, Paterson, Eric, Gebbing, Thomas, Sim, Allan, Abel, Claire

2007

Overview

$\\bullet$The aims of the study were to determine group specificity in microbial utilization of root-exudate compounds and whole rhizodeposition; quantify the proportions of carbon acquired by microbial groups from soil organic matter and rhizodeposition, respectively; and assess the importance of root-derived C as a driver of soil microbial community structure.$\\bullet$Additions of$^{13}C-labelled$root-exudate compounds to organic soil and steady-state labelling of Lolium perenne, coupled to compound-specific isotope ratio mass spectrometry, were used to quantify group-specific microbial utilization of rhizodeposition.$\\bullet$Microbial utilization of glucose and fumaric acid was widespread through the microbial community, but glycine was utilized by a narrower range of populations, as indicated by the enrichment of phospholipid fatty acid (PLFA) analysis fractions. In L. perenne rhizospheres, high rates of rhizodeposit utilization by microbial groups showed good correspondence with increased abundance of these groups in the rhizosphere.$\\bullet$Although rhizodeposition was not the quantitatively dominant C source for microbes in L. perenne rhizospheres, relative utilization of this C source was an important driver of microbial group abundance in organic soil.

• Publisher: Oxford, UK : Blackwell Publishing Ltd,Blackwell Science,Blackwell Publishing Ltd
• Subject: Acid soils / Agricultural soils / Biomass / carbon / Carbon Isotopes / community structure / fatty acids / Fatty Acids - metabolism / Fertilizers / fumaric acid / glucose / Grassland soils / Lolium - drug effects / Lolium - growth & development / Lolium - metabolism / Lolium - microbiology / Lolium perenne / Lolium perenne (ryegrass) / mass spectrometry / microbial communities / microbial community / Nitrogen - pharmacology / organic soil / Organic soils / phospholipid fatty acid (PLFA) / Phospholipids - metabolism / Plant Exudates - metabolism / Plant roots / Plant Roots - drug effects / Plant Roots - microbiology / Plant Shoots - drug effects / Plant Shoots - metabolism / Plants / Principal Component Analysis / rhizodeposition / Rhizosphere / Soil biochemistry / Soil biology / Soil Microbiology / Soil microorganisms / soil organic matter / steady-state ¹³C labelling / steady‐state 13C labelling