Oxides and oxy-sulphates as sources of micronutrients in the construction of the fertility of an oxisol.

In cerrado soils, the occurrence of micronutrient deficiency in several crops has been more and more frequent, being caused by the incorrect application of micronutrient sources and doses in the soil. Therefore, the objective of this work was to evaluate sources and doses of different water solubilities in the construction of micronutrient fertility in cerrado soil. The experiment was conducted in a greenhouse, the soil used was a dystrophic Red-Yellow Oxissol. The experimental design was in randomized block (DBC), arranged in a 6 x 2 factorial scheme, with three replications. The treatments consisted of control treatment and five doses for each source (0; 50; 100; 150; 200 and 250 kg ha -1 ) and two micronutrient sources of different water solubilization (FTE BR12 and Spene®). Spene® presented higher Cu, Zn, B and Mn availability compared to FTE BR12, regardless of the dose used. The agronomic efficiency of Cu, Zn and Mn availability with the use of the Spene® source is 29, 11 and 5% higher than the use of the FTE BR12 source. The use of Spene® in cerrado soils may be a promising alternative in the availability of micronutrient crops.