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| Titel |
Nanosiderite is effective to alleviate iron chlorosis in sensitive plants growing on calcareous soils |
| VerfasserIn |
I. Sánchez-Alcalá, M. C. Del Campillo, V. Barron, J. Torrent |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250064194
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| Zusammenfassung |
| Key words: siderite, iron chlorosis, calcareous soil, goethite, lepidocrocite
Nanosized siderite (FeCO3) prepared by mixing FeSO4 and K2CO3 solutions [either
alone or in presence of phosphate (siderites SID and SIDP, respectively)] was used in our
experiments. The products of oxidation of siderite in a calcite suspension were
goethite or a mixture of goethite and lepidocrocite when phosphate was present. These
iron oxides were nanosized and acid NH4oxalate-soluble, which suggested they
could be a good source of iron (Fe) for plants sensitive to Fe deficiency yellowing
(chlorosis).
To evaluate the effectiveness and long-term effects of suspensions of siderite mixed with
calcareous soil to prevent Fe chlorosis, a pot growth experiment was carried out with five
consecutive crops: chickpea (twice), peanut (twice) and strawberry. Suspensions of siderites
(SID and SIDP) were mixed with 220 g of soil at the beginning of the experiment at rates of
0.24, 0.46, 0.93 and 1.40 g siderite (0.12, 0.22, 0.45, and 0.67 g Fe) kg-1 soil. A control (no
Fe added) and a positive control (Fe-chelate as FeEDDHA before each cropping) were
included. The concentration of chlorophyll in the youngest leaves was estimated three times
for chickpea and peanut, and five times for strawberry via the SPAD value (SPAD 502
portable chlorophyll meter).
The SPAD for the control plants was lower than that for Fe-fertilized plants. For all crops,
times and siderite types, SPAD tended to systematically increase with increasing siderite
dose, and SID and SIDP had similar effectiveness. At harvest, the SPAD for the plants
fertilized with the highest siderite dose (1.40 g kg-1) did not differ significantly from that for
FeEDDHA-fertilized plants.
Our results suggest in summary that siderite is effective in preventing iron chlorosis and
has a long-lasting effect, as the likely result of the high specific surface and high solubility of
the crystalline Fe oxides resulting from its oxidation. Futhermore, siderite is readily prepared
in the field, not easily leached from the soil and environmentally safe, thus constituting a
good Fe fertilizer.
Acknowledgments: This work was funded by the Spain’s Ministerio de Ciencia e Innovación
and the European Regional Development Fund (Projects AGL 2005-06691-C02-01 and AGL
2008-05053-C02-02). |
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