EN
The method in which a pesticide is appied is of critical importance regarding the level of active ingredients residues in the grain of cereals. The herbicides applied in the autumn are decomposed during the growing season and at the moment of harvest the residues of the active ingredients were not detected. In the case of spring application of the same herbicides slight residues (10-3 mg•kg-1) of active ingredients were detected. Similar situation was observed when the same herbicides were used in spring and winter cereals in the spring. In view of the longer time available for the decomposition of the active ingredients of the herbicides, in the grain winter cereals lower residue levels were observed. The field trials have demonstrated that the level of active ingredient residues is positively correlated with herbicide rate. The lower residues in the grain of cereals were detected when the herbicide was applied at a lower rate.