A pot experiment was carried out to study the effect of trace elements on the biuret toxicity of maize, with the aim to provide theoretical basis for improving the urea-based compound fertilizer production and reducing the biuret toxicity. The results showed that the compound fertilizer with 2% and 4% biuret caused obvious toxicity on the maize. The plant became short, and the biomass decreased, and the toxicity phenomenon of maize would become more obvious when the biuret leve increased. Application of 5% EDTA-Zn and 0.4% B could reduce the toxicity of bi uret in fertilizers. The toxicity would be eliminated completely when the level of biuret was 2% in compound fertilizers, while the toxicity effects of 4% biuret was just alleviated to a certain extent. In addition, application of 2% amino acids with ureabased compound fertilizer could promote root absorption of biuret, and increase the biuret toxicity. In conclusion, the urea compound fertilizers with high biuret concentrations should be applied with appropriate trace elements to reduce the biuret dam age. It was suggested that the biuret content in the complex fertilizers for maize should be controlled below 2%, and appropriate trace elements should be applied at the same time.
