This title appears in the Scientific Report :
2008
Please use the identifier:
http://dx.doi.org/10.1007/s11104-007-9535-7 in citations.
Impact of phosphorus mineral source (Al-P or Fe-P) and pH on cluster-root formation and carboxylate exudation in Lupinus albus L.
Impact of phosphorus mineral source (Al-P or Fe-P) and pH on cluster-root formation and carboxylate exudation in Lupinus albus L.
Lupinus albus L. were grown in rhizoboxes containing a soil amended with sparingly available Fe-P or Al-P (100 mu g P g(-1) soil/resin mixture). Root halves of individual plants were supplied with nutrient solution (minus P) buffered at either pH 5.5 or 7.5, to assess whether the source of mineral-b...
Saved in:
Personal Name(s): | Shane, M. W. |
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Lambers, H. / Gawthray, G.R. / Kuhn, A. J. / Schurr, U. | |
Contributing Institute: |
Phytosphäre; ICG-3 |
Published in: | Plant and soil, 304 (2008) S. 169 - 178 |
Imprint: |
Dordrecht [u.a.]
Springer Science + Business Media B.V
2008
|
Physical Description: |
169 - 178 |
DOI: |
10.1007/s11104-007-9535-7 |
Document Type: |
Journal Article |
Research Program: |
Terrestrische Umwelt |
Series Title: |
Plant and Soil
304 |
Subject (ZB): | |
Publikationsportal JuSER |
Lupinus albus L. were grown in rhizoboxes containing a soil amended with sparingly available Fe-P or Al-P (100 mu g P g(-1) soil/resin mixture). Root halves of individual plants were supplied with nutrient solution (minus P) buffered at either pH 5.5 or 7.5, to assess whether the source of mineral-bound P and/or pH influence cluster-root growth and carboxylate exudation. The P-amended soil was mixed 3:1 (w/w) with anion-exchange resins to allow rapid fixation of carboxylates. Treatments lasted 10 weeks. Forty percent and 30% of the root mass developed as cluster roots in plants grown on Fe-P and Al-P respectively, but cluster-root growth was the same on root-halves grown at pH 5.5 or 7.5. Mineral-bound P source (Al- or Fe-P) had no influence on the types of carboxylates measured in soil associated with cluster roots-citrate (and trace amounts of malate and fumarate) was the only major carboxylate detected. The [citrate] in the rhizosphere of cluster roots decreased with increased shoot P status (suggesting a systemic effect) and also, only for plants grown on Al-P, with decreased pH in the root environment (suggesting a local effect). In a separate experiment using anion exchange resins pre-loaded with malate or citrate, we measured malate (50%) and citrate (79%) recovery after 30 days in soil. We therefore, also conclude that measurements of [citrate] and [malate] at the root surface may be underestimated and would be greater than the 40- and 1.6-mu mol g(-1) root DM, respectively estimated by us and others because of decomposition of carboxylates around roots prior to sampling. |