Murdoch University Research Repository

Welcome to the Murdoch University Research Repository

The Murdoch University Research Repository is an open access digital collection of research
created by Murdoch University staff, researchers and postgraduate students.

Learn more

Increasing the size of the microbial biomass altered bacterial community structure which enhances plant phosphorus uptake

Brusetti, L., Shen, P., Murphy, D.V., George, S.J., Lapis-Gaza, H., Xu, M. and Gleeson, D.B. (2016) Increasing the size of the microbial biomass altered bacterial community structure which enhances plant phosphorus uptake. PLoS ONE, 11 (11). Art. e0166062.

[img]
Preview
PDF - Published Version
Download (2MB) | Preview
Free to read: https://doi.org/10.1371/journal.pone.0166062
*No subscription required

Abstract

Agricultural production can be limited by low phosphorus (P) availability, with soil P being constrained by sorption and precipitation reactions making it less available for plant uptake. There are strong links between carbon (C) and nitrogen (N) availability and P cycling within soil P pools, with microorganisms being an integral component of soil P cycling mediating the availability of P to plants. Here we tested a conceptual model that proposes (i) the addition of readily-available organic substrates would increase the size of the microbial biomass thus exhausting the pool of easily-available P and (ii) this would cause the microbial biomass to access P from more recalcitrant pools. In this model it is hypothesised that the size of the microbial population is regulating access to less available P rather than the diversity of organisms contained within this biomass. To test this hypothesis we added mixtures of simple organic compounds that reflect typical root exudates at different C:N ratios to a soil microcosm experiment and assessed changes in soil P pools, microbial biomass and bacterial diversity measures. We report that low C:N ratio (C:N = 12.5:1) artificial root exudates increased the size of the microbial biomass while high C:N ratio (C:N = 50:1) artificial root exudates did not result in a similar increase in microbial biomass. Interestingly, addition of the root exudates did not alter bacterial diversity (measured via univariate diversity indices) but did alter bacterial community structure. Where C, N and P supply was sufficient to support plant growth the increase observed in microbial biomass occurred with a concurrent increase in plant yield.

Item Type: Journal Article
Publisher: Public Library of Science
Copyright: © 2016 Shen et al.
URI: http://researchrepository.murdoch.edu.au/id/eprint/66392
Item Control Page Item Control Page

Downloads

Downloads per month over past year