A one‐decade update on chelated metals for supplying micronutrients to crops—

Abstract

Synthetic chelating agents have been available for plant nutrition for 30 years. Without them agriculture would be virtually irtpossible in some locations because of extreme iron deficiency. Generally, however, chelating agents are too expensive for use in general field agriculture except where their efficiency of utilization can be greatly increased such as with drip irrigation techniques. Chelating agents also find usage in hydroponic operations as a means of supplying iron to plants. Zinc chelates are sometimes used in hydroponics but probably are not necessary. Chelates are commonly used in liquid fertilizers to keep zinc, manganese and copper in a soluble form in them so that they can be applied in solution and with flow equipment. It is generally accepted that chelating agents function in soil by keeping micronutrients soluble in soil and by facilitating their movement in soil to plant roots. Even after 30 years there is still sons controversy about the interactions of chelating agents with plants.