THE EFFECT OF FOLIAR FERTILIZATION WITH UREA UPON THE CONTENT OF MACRONUTRIENTS IN CAMBIC CHERNOZEM

Sunflower and maize are two crops of particular importance, especially in the current context of the food crisis, cultivated on large areas worldwide, used both for animal and human nutrition. This study proposed to test the effectiveness of several types of foliar fertilizers with urea, for the two previously mentioned crops, in the pedo-climatic conditions of West of Romania, and the type of soil chosen for experimentation was Cambic Chernozem. The chemical compounds used for fertilizing crops were different urea solutions. As for the pH of urea solutions, they all have a value of 7.5 pH units, which places them in the neutral reaction class. In order to see if these types of fertilizers have an effect on the soil, samples were collected before the crops were sown but also after they were harvested. The indicators determined according to the current methodologies were: soil pH in aqueous solution, and the content of main macronutrients: total nitrogen, phosphorus and potassium. After analyzing the obtained results, a slight decrease in the concentration of these macronutrients in the soil was found, as well as an insignificant decrease in the pH values of the soil.