Tracking Se Assimilation and Speciation through the Rice Plant - Nutrient Competition, Toxicity and Distribution.
Up to 1 billion people are affected by low intakes of the essential nutrient selenium (Se) due to low concentrations in crops. Biofortification of this micronutrient in plants is an attractive way of increasing dietary Se levels. We investigated a promising method of Se biofortification of rice seedlings, as rice is the primary staple for 3 billion people, but naturally contains low Se concentrations. We studied hydroponic Se uptake for 0-2500 ppb Se, potential phyto-toxicological effects of Se and the speciation of Se along the shoots and roots as a function of added Se species, concentrations and other nutrients supplied. We found that rice germinating directly in a Se environment increased plant-Se by factor 2-16, but that nutrient supplementation is required to prevent phyto-toxicity. XANES data showed that selenite uptake mainly resulted in the accumulation of organic Se in roots, but that selenate uptake resulted in accumulation of selenate in the higher part of the shoot, which is an essential requirement for Se to be transported to the grain. The amount of organic Se in the plant was positively correlated with applied Se concentration. Our results indicate that biofortification of seedlings with selenate is a successful method to increase Se levels in rice.
Institute of Applied Geosciences (AGW), Karlsruhe Institute of Technology (KIT), Adenauerring 20b, D-76131 Karlsruhe, Germany.
Alexandra K
0000-0003-4610-3403
AK
Nothstein
Institute of Applied Geosciences (AGW), Karlsruhe Institute of Technology (KIT), Adenauerring 20b, D-76131 Karlsruhe, Germany.
Elisabeth
E
Eiche
Molecular Cell Biology, Botanical Institute, and Center for Functional Nanostructures (CFN), Karlsruhe, Institute of Technology (KIT), Kaiserstraße 2, D-76131 Karlsruhe, Germany.
Michael
M
Riemann
Molecular Cell Biology, Botanical Institute, and Center for Functional Nanostructures (CFN), Karlsruhe, Institute of Technology (KIT), Kaiserstraße 2, D-76131 Karlsruhe, Germany.
Peter
P
Nick
Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland.|Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, Universitätsstraße 16, CH-8092 Zürich, Switzerland.
Lenny H E
LH
Winkel
ANKA Synchrotron Radiation Facility, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany.
Jörg
J
Göttlicher
ANKA Synchrotron Radiation Facility, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany.
Ralph
R
Steininger
Molecular Cell Biology, Botanical Institute, and Center for Functional Nanostructures (CFN), Karlsruhe, Institute of Technology (KIT), Kaiserstraße 2, D-76131 Karlsruhe, Germany.
Rita
R
Brendel
Institute of Applied Geosciences (AGW), Karlsruhe Institute of Technology (KIT), Adenauerring 20b, D-76131 Karlsruhe, Germany.
Matthias
M
von Brasch
Institute of Applied Geosciences (AGW), Karlsruhe Institute of Technology (KIT), Adenauerring 20b, D-76131 Karlsruhe, Germany.
Gabriele
G
Konrad
Institute of Applied Geosciences (AGW), Karlsruhe Institute of Technology (KIT), Adenauerring 20b, D-76131 Karlsruhe, Germany.
Thomas
T
Neumann
D001693:Biological Transport, Active; D018525:Germination; D006801:Humans; D018527:Hydroponics; D018977:Micronutrients / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000633:toxicity; D012275:Oryza / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D018520:Plant Shoots / Q000378:metabolism; D036226:Seedlings / Q000378:metabolism; D064586:Selenic Acid / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000633:toxicity; D012643:Selenium / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000633:toxicity
D018977:Micronutrients; D012643:Selenium; D064586:Selenic Acid