In recent years, a big problem for agriculture is the shortage of available micronutrients in the soil, thus reducing yields. This deficiency is due to the intensification of agriculture, cultivation of new species of plants require fertilization and a significant share of soils with low content of available micronutrients, which is why in recent years looking for the appropriate forms in which they can be applied to not have a negative impact on the environment. Of particular importance in the field of micronutrient fertilizers gained chelates. These compounds are characterized by stability. Chelating agents stabilize the cations of microelements in a wide pH range. Their application optimizes supplement micronutrient deficiency. Adaptation of nutrients to the needs of the plants can reduce the negative impact on the environment, without causing soil salinity, as in the case of salt micronutrients. Can be applied to both soil and foliar application. They are produced in the form of liquid or fine-crystalline. In the European Union are set chelating agents used as additives for liquid fertilizers. These are synthetic compounds belonging to the aminepolycarboxylic compounds (APCAs) which form stable complexes which are soluble in water. APCAs form chelates of trace elements in a molar ratio 1:1. The most commonly used component is the disodium salt of ethylenediaminetetraacetic acid (EDTA). The Regulation of the European Parliament and of the Council EC No 2003/2003 of 13 October 2003 includes the requirements for chelates used in agriculture. In accordance with these requirements complex the trace element level should be at least 80 % of the declared water-soluble, the total metal content. Download time micronutrient by the plant in the soil environment should correspond to the period degradability. Too low biodegradability may adversely affect the environment, causing mobilization heavy metals from bottom sediments and lead to phytotoxic complexes. Formal requirements resulted in the continued search for new chelating agents, and improving the technology used. The aim of the study was to determine the degree of complexation of the selected ions of micronutrients with chelating substance at different reaction times. The molar ratio of metal-ligand equal to 1:1. The degree of complexation was determined by differential pulse voltammetry. Was selected micronutrient zinc. Comparison was made to a compound belonging to the group of derivatives of aminepolycarboxylic compounds and for substances of natural origin – amino acid. These studies will help determine the optimal response time complexation of micronutrients by chelating agents commonly used in the fertilizer industry.
