02076naa a2200265 a 450000100080000000500110000800800410001902400510006010000190011124500580013026000090018852013610019765000140155865000090157265000100158165000170159165000150160865000090162365300340163265300140166670000180168070000250169870000220172377300650174512173272022-06-02       2008    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1080/019041608022449022DOI1 aFAGERIA, N. K.  aIron toxicity in lowland rice.h[electronic resource]  c2008  aLowland rice is a staple food for more than 50% world population. Iron toxicity is one of the main nutritional disorders, which limits yield of lowland rice in various parts of the world. The toxicity of iron is associated with reduced soil condition of submerged or flooded soils, which increases concentration and uptake of iron (Fe2+). Higher concentration of Fe2+ in the rhizosphere also has antagonistic effects on the uptake of many essential nutrients and consequently yields reduction. In addition to reduced condition, increase in concentration of Fe2+ in submerged soils of lowland rice is associated with iron content of parent material, oxidation-reduction potential, soil pH, ionic concentration, fertility level, and lowland rice genotypes. Oxidationreduction potential of highly reduced soil is in the range of ?100 to ?300 mV. Iron toxicity has been observed in flooded soils with a pH below 5.8 when aerobic and pH below 6.5 when anaerobic. Visual toxicity symptoms on plants, soil and plant tissue test are major diagnostic techniques for identifying iron toxicity. Appropriate management practices like liming acid soils, improving soil fertility, soil drainage at certain growth stage of crop, use of manganese as antagonistic element in the uptake of Fe2+ and planting Fe2+ resistant rice cultivars can reduce problem of iron toxicity.  aoxidation  arice  aArroz  aOryza Sativa  aOxidação  aSolo  aDTPA iron extracting solution  aReduction1 aSANTOS, A. B.1 aBARBOSA FILHO, M. P.1 aGUIMARÃES, C. M.  tJournal of Plant Nutritiongv. 31, n. 9, p. 1676-1697, 2008.