Assessment of Efficiency of Nutrient Uptake of Different Sources of Zn, Mn, Cu and B in Zea mays

Advances in plant nutrition can be achieved by improving the delivery of micronutrients to the plants. The objective of this research was to compare the efficiency of uptake of different sources of zinc, copper and manganese (sulfates, Ethylenediaminetetraacetic acid (EDTA) and oxides) and boron (boric anhydride and colemanite). We conducted all experiments in maize, repeated the experiment twice, using five replicates per treatment, and used two different media. Results showed that for cations, the soluble sources of micronutrients (sulfate and EDTA) in both media were more efficiently taken up. One-way ANOVA with post hoc Tukey for multiple comparisons of means (95% confidence level) was used for all statistical analyses. Sulfate sources were significantly different when compared to the negative control and to the oxide sources. EDTA sources were significantly different when compared to the negative control and to the oxide sources. Oxide sources were not significantly different from the negative control. For boron, we found a similar trend, with boric anhydride being significantly different when compared to the negative control and to colemanite. Colemanite was significantly different when compared to the negative control. This study generated important information about uptake of soluble and insoluble sources of four micronutrients that can be used for the development of new formulations. Keywords: zinc; copper; manganese; boron; sulfates; EDTA; oxides; boric anhydride; colemanite; nutrient uptake