Work

Iron Solubility and Uptake in Fava Bean and Maize as a Function of Iron Chelates under Alkaline Hydroponic Conditions

Year: 2025

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide Iron-EDTA becomes unstable above pH 6.5, resulting in competition among metal ions (Fe, Cu, Zn, and Mn) for EDTA and reduced Fe availability. This study examined nutrient precipitation dynamics and interactions between chelated and sulfate forms of Zn, Mn, and Cu with Fe-EDTA in fava bean and maize under increasing alkalinity (0, 5, and 15 mM NaHCO 3 ). In fava bean, chelated micronutrients significantly increased shoot Fe, P, and Zn concentrations and improved metabolic activity and oxidative stress tolerance. Maize was more sensitive to alkalinity but showed similar nutrient responses at 5 mM NaHCO 3 . Speciation modeling (MINEQL+5.0) indicated Fe displacement from Fe-EDTA at high pH, forming insoluble FePO 4 and Fe(OH) 3 . Incubation studies demonstrated that Fe-HBED maintained higher Fe, Ca, and P solubility than Fe-EDTA and Fe-DTPA under alkaline conditions. SEM-EDX analysis linked stable Fe chelates to lower P in precipitates. Results highlight Fe-HBED’s effectiveness in ensuring Fe and P availability under alkalinity.

Source: Journal of Agricultural and Food Chemistry

DOI: 10.1021/acs.jafc.5c08914

Authors: Muhammad Faizan Ilyas, Muhammad Imran, Asif Naeem, Arjen M. Reichwein, Karl Hermann Mühling

Institution: Christian-Albrechts-Universität zu Kiel

Language: English

Topic: Plant Micronutrient Interactions and Effects

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: hybrid

Estimated APC paid: $4,500