Evaluation of soil EDTA applications on crop performance and uptake of macro- and micronutrients by agricultural crops

Chelates such as ethylenediaminetetraacetic acid (EDTA)enter the environment from various sources but its impacton crop growth and mineral uptake has been evaluated only sporadically. In a pot experiment with graded EDTA applications the impact of free EDTA on crop performance, macro- and microelement uptake was assessed. The sensitivity towards EDTA decreased from sunflower > oilseed rape > maize. Maize was the least sensitive crop showing no visual toxicity symptoms, however,a reduction in biomass development. Incomparison, oilseed rape and sunflower displayed necrotic lesions on their leaves and biomass development was significantly reduced when higher rates of EDTA were applied. Soil EDTA appli­cation increased the uptake of Mn and Zn in shoots of all three crops and in roots of maize and sunflower. In maize EDTA increased not only the uptake of Mn and Zn, but also all other investigated micronutrients in shoots with the only exception of copper. In oilseed rape EDTA applications increased the uptake of Cu, Mn and Zn in shoots while the Fe, Mn and Mo content decreased in roots. Changes in the micronutrient content in shoots of sunflowers were similar to that in oilseed rape. In roots EDTA increased the Mn uptake. Next to micronutrients EDTA influenced the macronutrient uptake of the tested crop plants.