Biofortification of maize with micronutrients by Spirulina

The aim of the present work was to examine the effect of the application of Spirulina platensis post-extraction residues enriched with Zn(II), Mn(II), Cu(II) via biosorption as micronutrient fertilizer for the biofortification of maize grains with micronutrients in field tests. As a nominal dose 2.5 kg ha(-1) of zinc, 1.0 kg ha(-1) of manganese and 0.5 kg ha(-1) of copper were applied. The preparation was applied also in higher doses (150%, 200%) to investigate agronomic biofortification of maize grains. In field trials, obtained grain yield (7.2 Mg ha(-1) for Spirulina 100%) was higher than in control group (6.2 Mg ha(-1)) and commercial reference product (6.6 Mg ha(-1)). For the same dose of micronutrients, their bioavailability was higher for bio-preparations than for reference fertilizer. The highest content of micronutrients delivered to plants (2.15 mg kg(-1) - Cu, 7.07 mg kg(-1) - Mn, 29.0 mg kg(-1) - Zn) was observed for maize grains fertilized with preparation of Spirulina 150%, which signifies that biofortified maize grain was obtained. Corn grains biofortified with micronutrients can be used as staple food or feed preventing from micronutrient malnutrition. The application of micronutrient biocomponents based on Spirulina biomass allows to manufacture a valuable fertilizer with bioavailable micronutrients.