APPLICATION OF MICRONUTRIENTS AS P-FERTILIZER COATINGS FOR PRECISION
DISTRIBUTION IMPROVES NUTRIENTS USE EFFICIENCY IN SOYBEAN CROP
ENVIRONMENT
Abstract
Problems related to the uniform distribution of micronutrients and their
low use efficiency are common. One possible solution is to add
micronutrients as fertilizer coating. However, it is necessary to
comprehend the use of micronutrients applied via coating and their
nutrition in the phenological stages of soybean. Therefore, the
objectives of this study were to quantify the diffusion and the
availability of P, B, Cu, Mn, and Zn in soil after the incubation of
fertilizers coated with micronutrients, as well as to evaluate the
nutrition, yield, and recovery of nutrients at different soybean
phenological stages under controlled and field conditions. The
treatments were MAP and NPS coated with Maxxi-Phós® polymer and one of
the micronutrient sources: Wolftrax®, Microsol®, or MIB Precise®. The
P-diffusion ranged from 5.58 to 18.88 mm. The nutrient recovery varied
according to the phenological stage of the plants with emphasis on the
V4 stage, which resulted in the following recoveries: B (13.89 to
0.65%), Cu (62.84 to 6.73%), Mn (3.36 to 0.73%), Zn (2.34 to 0.01%).
Nutrient exports by soybean were: 55.7 kg ha-1, 209.6, 109, 216.7, and
64.3 g ha-1 of P2O5, B, Mn, Zn, and Cu, respectively. Under field
conditions, there was a significant absorption of B, Mn, and Zn at
stages R1 to R5.1, while for Cu it was between V4 and R1. The NPS + MIB
Precise® fertilizer showed lower accumulations and yield, indicating
lower solubility of micronutrients supplied via oxysulfate. The
technologies were able to replace the exported nutrients by the soybean.