The market is steadily increasing the range of products aimed at the plant production to increase plant health by inducing processes of defense and its development. Most of them are products based on natural substances or microorganisms, which compete with pathogens. The aim of research was to evaluate the use of plant protection products based on Pythium oligandrum to seed vegetable dressing (dry and wet) and its impact on the further development of the plants. It was found that the type of treatment did not affect the germination of carrots. For radish, as is the case of tomato the increase of the number of emergence after dry dressing was observed. Among the plants that emerged the highest number of dead plants growing in the soil it was observed after dry dressing of carrots seeds, in the case of radishes there was no effect on the number of dead plants. For tomato, it was observed that the wet dressing strongly contributed to the increased necrosis seedlings. The plants growing in next time - carrots, radishes and tomatoes, subject to treatment dry or wet, strongly developed aboveground and underground parts in comparison to untreated control plants.