Root exudates induced coupled carbon and phosphorus cycling in a soil with low phosphorus availability
AffiliationDepartment of Environmental Science, University of Arizona
Mineral associated organic matter
MetadataShow full item record
PublisherSpringer Science and Business Media LLC
CitationJoshi, S. R., Tfaily, M. M., Young, R. P., & McNear Jr, D. H. (2023). Root exudates induced coupled carbon and phosphorus cycling in a soil with low phosphorus availability. Plant and Soil, 1-20.
JournalPlant and Soil
Rights© The Author(s), under exclusive licence to Springer Nature Switzerland AG 2023.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractBackground and aims: The amount and type of root exudates can influence P availability in the rhizosphere directly by desorption or dissolution of soil minerals, or indirectly by decomposition of soil organic matter (SOM). This study aimed to determine the mechanisms by which specific root exudates influence the distribution and availability of P in soils with low P availability. Methods: Water, glucose, alanine, and oxalate were delivered through a simulated root into soils for 15 days. Zymography and planar optodes were used to image potential phosphatase activity, and O2 and pH distribution, respectively. Soils were analyzed for resin extractable inorganic P (Pi), dissolved organic C (DOC), water soluble Fe, and Al, and microbial community structure. Characterization of SOM and P were conducted using ultra-high resolution mass spectrometry and 31P solution nuclear magnetic resonance (NMR), respectively. Results: The addition of oxalate resulted in the greatest resin extractable Pi, DOC, and water-soluble Fe, and Al compared to the other exudates suggesting destabilization of mineral associated organic matter (MAOM) and release of organic P (Po). Both 31P solution NMR and ultra-high resolution mass spectrometry analysis provided evidence of mineralization of Po released from the destabilization of MAOM. Conclusion: The study demonstrates the important role microbial and plant-derived metal chelating ligands play in destabilizing MAOM, releasing SOM and importantly Po, that when mineralized may contribute to increasing Pi availability in soils with low P availability.
Note12 month embargo; first published 29 December 2023
VersionFinal accepted manuscript