Iron and zinc isotope fractionation during uptake and translocation in rice (Oryza sativa) grown in oxic and anoxic soils

A - Papers appearing in refereed journals

Arnold, T., Markovic, T., Kirk, G. J. D., Schonbachler, M., Rehkamper, M., Zhao, F-J. and Weiss, D. J. 2015. Iron and zinc isotope fractionation during uptake and translocation in rice (Oryza sativa) grown in oxic and anoxic soils. Comptes Rendus Geoscience. 347 (7-8), pp. 397-404.

AuthorsArnold, T., Markovic, T., Kirk, G. J. D., Schonbachler, M., Rehkamper, M., Zhao, F-J. and Weiss, D. J.
Abstract

Stable isotope fractionation is emerging quickly as a powerful novel technique to study metal uptake and translocation in plants. Fundamental to this development is a thorough understanding of the processes that lead to isotope fractionation under differing environmental conditions. In this study, we investigated Zn and Fe isotope fractionation in rice grown to maturity in anaerobic and aerobic soils under greenhouse conditions. The overall Zn isotope fractionation between the soil and above ground plant material was negligible in aerobic soil but significant in anaerobic soil with isotopically lighter Zn in the rice plant. The observed range of fractionation is in line with previously determined fractionations of Zn in rice grown in hydroponic solutions and submerged soils and emphasizes the effect of taking up different chemical forms of Zn, most likely free and organically complexed Zn. The Zn in the grain was isotopically lighter than in the rest of the above ground plant in rice grown in aerobic and anaerobic soils alike. This suggests that in the course of the grain loading and during the translocation within the plant important biochemical and/or biophysical processes occur. The isotope fractionation observed in the grains would be consistent with an unidirectional controlled transport from shoot to grain with a fractionation factor of α ≈ 0.9994. Iron isotopes showed an isotopic lighter signature in shoot and grain compared to the bulk soil or the leachate in aerobic and anaerobic soils alike. The negative direction of isotopic fractionation is consistent with possible changes in the redox state of Fe occurring during the uptake and translocation processes. The isotope fractionation pattern between shoots and grain material are different for Zn and Fe which finally suggests that different mechanisms operate during translocation and grain-loading in rice for these two key micronutrients.

KeywordsIsotopes; Rice (Oryza sativa); Anaerobic Soils; Iron; Zinc
Year of Publication2015
JournalComptes Rendus Geoscience
Journal citation347 (7-8), pp. 397-404
Digital Object Identifier (DOI)doi:10.1016/j.crte.2015.05.005
Open accessPublished as bronze (free) open access
FunderBiotechnology and Biological Sciences Research Council
Publisher's version
Output statusPublished
Publication dates
Online02 Jul 2015
Publication process dates
Accepted11 May 2015
PublisherElsevier France-Editions Scientifiques Medicales Elsevier
ISSN1631-0713

Permalink - https://repository.rothamsted.ac.uk/item/8v1y7/iron-and-zinc-isotope-fractionation-during-uptake-and-translocation-in-rice-oryza-sativa-grown-in-oxic-and-anoxic-soils

25 total views
4 total downloads
0 views this month
0 downloads this month
Download files as zip