Remediation of iron chlorosis by the addition of Fe-o,o-EDDHA in the nutrient solution applied to soilless culture

Abstract

The aim of this study was to evaluate the remediation of ferric chlorosis using by iron (Fe)-o,o-EDDHA in fertigation of soilless crops compared with Fe-EDTA (ethylene diamine tetra acetic acid) and its effects on production. Two separate greenhouse experiments were conducted in slab or bag cultures using the tomato (Lycopersicon esculentum Mill. cv. Daniela) and green bean crops (Phaseolus vulgaris L. cv. Maite) in Almeria (southeast Spain). The crops were subjected to the following experimental setup: 1) At first phase, all plants were treated with a standard nutrient solution and Fe was supplied as Fe-EDTA. 2) No Fe was supplied in the nutrient solution to bean crops 46 days after transplanting. For tomato plants, this element was eliminated from the nutrient solution since 102 days after transplanting. In this phase, Fe-EDTA was supplied to the control plants (T1). This phase was ended when signs of ferric chlorosis appeared on the leaves. 3) The ferric chlorosis was remediated with either Fe-EDTA (T2) or Fe-o,o-EDDHA (T3). The T4 group did not receive any supplements. The total tomato and bean production was improved after the Fe deficiency had been corrected by either EDTA and Fe o,o-EDDHA supplements in the fertigation of these crops. The synthetic Fe o,o-EDDHA chelate alleviated Fe deficiency by increasing the amount of iron in the rhizosphere and its supply to the leaves and petioles. Consequently, the decrease in tomato and bean production resulting from ferric chlorosis could be prevented. As a conclusion, the remediation of ferric chlorosis through fertigation with Fe o,o-EDDHA is as effective as the use of traditional Fe-EDTA.