Nanocomposite substances based on natural matrices -arabinogalactan, starch, carrageenan -were used in the work. Studies have been conducted on the effect of nanocomposites on the pathogen of ring rot of potatoes, as well as the growth and development of plants in vitro. The data obtained did not show a negative effect on plants, but showed an antibacterial effect on the growth and biofilm formation of bacteria.