Micronutrients in coated phosphate fertilizer improve precision distribution and nutrient use efficiency of soybean

Abstract

AbstractChallenges regarding uniform micronutrient distribution and P‐use efficiency in agricultural soils are common. Micronutrients can be added as coated P fertilizers, creating multi‐nutrient fertilizers for crops to address this issue. The objective of this study was to quantify the diffusion and availability of P, B, Cu, Mn, and Zn in coated P fertilizers. Another objective was to evaluate the nutrient uptake, partitioning, and yield of soybeans. Treatments were monoammonium phosphate and NPS (nitrogen, phosphorus, sulfur) fertilizer coated with Maxxi‐Phós and either Wolftrax, Microsol, or MIB Precise. Applied concentrations of B and Cu varied between 0.15% and 0.05%. The Mn and Zn ranged from 0.45% to 0.15%. Nutrient accumulation and recovery were assessed in the greenhouse and field trials. P diffusion ranged from 5.58 to 18.88 mm in 336 h. Micronutrient use efficiencies varied according to the soybean (Glycine max) phenological stages, with emphasis on the V4 stage, which resulted in the following values: B (0.65% to 13.89%), Cu (6.73% to 62.84%), Mn (0.73% to 3.36%), and Zn (0.01% to 2.34%). Nutrient exports were: 55.7 kg of P2O5 ha−1, 209.6 g of B ha−1, 109 g of Mn ha−1, 216.7 g of Zn ha−1, and 64.3 g of Cu ha−1. There was significant absorption (p ≤ 0.05) of B, Mn, and Zn at stages R1–R5.1 in the field trial, whereas it was from V4 to R1 for Cu. As a multi‐nutrient fertilizer for soybeans, micronutrient‐coated P fertilizers could replace exported nutrients.