To determine the allelopathic effects of mycelial biomass of investigated strains was used a modified sandwich method: between two layers of agar medium was added 0.1 g of dry crushed biomass, followed by the introduction of seeds on the top layer. To determine the effect of methanol and ethyl acetate extracts, extract - soaked filter paper discs in sterile Petri dishes were used, to which 2 ml of sterile water was added after evaporation of the solvents, then seeds were added. Aqueous were adjusted to 2 ml with sterile water and impregnated the filter paper discs, after which the seeds were added. Biomass of all investigated strains shows allelopathic influence: the strongest - mycelium G. tsugae Murrill 2024 - inhibits plants growth by 80.9%, the weakest - G. carnosum Pat. 2502 - inhibits plants growth by 30.7% compared to control. Addition of 20 μl of G. sinense J.D. Zhao, L.W. Hsu & X.Q. Zhang 2516 aqueous extract stimulates shoot growth compared to the control by 19.3%. Ethyl acetate extracts of G. tsugae 2024 showed the highest allelopathic influence, which increased with increasing concentration of the extract - at a concentration of 100 μl, plant growth was inhibited by 100%.Keywords: Ganoderma, Ganoderma extracts, mushroom allelopathy, plant growth regulation, sandwich metod.