Microbial decomposition of <sup>13</sup>C- labeled phytosiderophores in the rhizosphere of wheat

Author(s)
Eva Oburger, Barbara Gruber, Wolfgang Wanek, Andrea Watzinger, Christian Stanetty, Yvonne Schindlegger, Stephan Hann, Walter D C Schenkeveld, Stephan Kraemer, Markus Puschenreiter
Abstract

Being low molecular weight carbon (LMW-C) compounds, phytosiderophores (PS) released by strategy II plants are highly susceptible to microbial decomposition. However, to date very little is known about the fate of PS in soil. Using in-house synthesized 13C4-2'-deoxymugineic acid (DMA), the main PS released by wheat, we investigated DMA mineralization dynamics, including microbial incorporation into phospholipid fatty acids (PLFA), in the wheat rhizosphere and bulk soil of two alkaline and one acidic soil. Half-lives of the intact DMA molecule (3-8 h) as well as of DMA-derived C-compounds (8-38 days) were in the same order of magnitude as those published for other LMW-C compounds like sugars, amino acids and organic acids. Combining mineralization with PLFA data showed that between 40 and 65% of the added DMA was either respired or incorporated into soil microbial biomass after 24 h, with the largest part of total incorporated DMA-13C being recovered in gram negative bacteria. Considering root growth dynamics and that PS are mainly exuded from root tips, the significantly slower mineralization of DMA in bulk soil is of high ecological importance to enhance the Fe scavenging efficiency of PS released into the soil.

Organisation(s)
External organisation(s)
University of Natural Resources and Life Sciences, Austrian Institute of Technology, Technische Universität Wien
Journal
Soil Biology and Biochemistry
Volume
98
Pages
196-207
No. of pages
12
ISSN
0038-0717
DOI
https://doi.org/10.1016/j.soilbio.2016.04.014
Publication date
07-2016
Peer reviewed
Yes
Austrian Fields of Science 2012
106022 Microbiology
Keywords
ASJC Scopus subject areas
Soil Science, Microbiology
Portal url
https://ucrisportal.univie.ac.at/en/publications/7687c4ea-1af0-4595-bc20-6efc9d015dac