The effects of soil phosphorus content on plant microbiota are driven by the plant phosphate starvation response
Year: 2019
Type: article
Abstract: Phosphate starvation response (PSR) in nonmycorrhizal plants comprises transcriptional reprogramming resulting in severe physiological changes to the roots and shoots and repression of plant immunity. Thus, plant-colonizing microorganisms-the plant microbiota-are exposed to direct influence by the soil's phosphorus (P) content itself as well as to the indirect effects of soil P on the microbial niches shaped by the plant. The individual contribution of these factors to plant microbiota assembly remains unknown. To disentangle these direct and indirect effects, we planted PSR-deficient Arabidopsis mutants in a long-term managed soil P gradient and compared the composition of their shoot and root microbiota to wild-type plants across different P concentrations. PSR-deficiency had a larger effect on the composition of both bacterial and fungal plant-associated microbiota than soil P concentrations in both roots and shoots. To dissect plant-microbe interactions under variable P conditions, we conducted a microbiota reconstitution experiment. Using a 185-member bacterial synthetic community (SynCom) across a wide P concentration gradient in an agar matrix, we demonstrated a shift in the effect of bacteria on the plant from a neutral or positive interaction to a negative one, as measured by rosette size. This phenotypic shift was accompanied by changes in microbiota composition: the genus Burkholderia was specifically enriched in plant tissue under P starvation. Through a community drop-out experiment, we demonstrated that in the absence of Burkholderia from the SynCom, plant shoots accumulated higher ortophosphate (Pi) levels than shoots colonized with the full SynCom but only under Pi starvation conditions. Therefore, Pi-stressed plants are susceptible to colonization by latent opportunistic competitors found within their microbiome, thus exacerbating the plant's Pi starvation.
Source: PLoS Biology
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDGs: Zero hunger, Life on land
Open Access status: gold
Estimated APC paid: $3,000
Awards: Designing robust synthetic microbiota for increasing plant productivity, INSPIRE Track 2: Defining the Organizational Principles of Microbial Communities Colonizing Plant Roots, Synthetic bacterial communities to dissect and direct plant microbiome function, SYSTEMS ANALYSIS OF THE PHYSIOLOGICAL AND MOLECULAR MECHANISMS OF SORGHUM NITROGEN USE EFFICIENCY, WATER USE EFFICIENCY AND INTERACTIONS WITH THE..., G5021668114, G7692083976
OpenAlex ID: W2988737464