Environmentally benign Fe chelates in plant nutrition

Summary

The low solubility of iron (Fe) depresses plant growth in calcareous soils. In order to improve Fe availability, calcareous soils are treated with synthetic ligands, such as ethylenediaminetetraacetic acid (EDTA) and ethylenediimonobis(2-hydroxyphenyl)acetic acid (EDDHA). However, high expenses may hinder their use (EDDHA), and the recalcitrance of EDTA against biodegradation may increase the potential of cadmium (Cd) and lead (Pb) leaching. This study evaluated the ability of biodegradable ligands, i.e. different stereoisomers of ethylenediaminedisuccinic acid (EDDS), to provide Fe for lettuce (Lactuca sativa L.) and ryegrass (Lolium perenne cv. Prego), their effects on uptake of other elements and solubility in soils and their subsequent effects on the activity of oxygen-scavenging enzymes in lettuce.