The effect of secondary metabolites isolated from two representatives of fem. Scrophulariaceae, namely, Veronica officinalis L. and Linaria genistifolia L., having a growth regulating effect, on the development of phytopathogenic fungi of Alternaria alternata (Fr.) Keissl under laboratory testing conditions was studied. These substances were used to increase the energy of germination and the general germination of tomato seeds due to the presowing soaking of the latter in aqueous solutions of these compounds. Analysis of the results showed that the substances used in the experiment inhibited the development of mycelium of fungi, and the increase in concentration had a positive effect on the effectiveness of their action. Aqueous solution of verofosides in 5x10-2% concentration showed the highest fungicidal activity.