The testing was carried out in an orchard plum Stanley, with a planting scheme of 5x3 m, the harmfulness of dangerous diseases such as clasterosporium or perforated spotting (Clasterosporium carpophilum Aderch.), polystigmosis or red spotting, spotting (Polystigma rubrum Pers.) and moniliosis (Monilia spp.) was observed. The objects to be tested were a biological preparation - fungicide Carbecol, with the active substance sodium bicarbonate and Funecol SL with the active substance copper sulfate 79 g/l. The experiment scheme included 4 variants, in 2 of which preparations were tested Carbecol- 4 kg/ha, Funecol SL 3 l/ha in 2 different doses, in one variant - a chemical standard and a variant (trees were sprayed with clean drinking water without adding an fungicide). The fungicide used in production – Pencozeb 75 WG – 2 kg/ha served as the Standard.