The article starts with literature review on secondary metabolites, namely the iridoids contained in Linaria species (Scrophulariaceae). It describes the biological activity of the iridoid glycosides; the importance and the benefits of the secondary metabolites and their eventual application in organic plant cultivation. Is further elucidated the profile of the biologically active substances predominant in the purified extract of Linaria genistifolia (L.) Mill., named by us genistifoliosides. Are investigated the biological activity and the stimulating effect of genistifolioside aqueous solution in concentration 0.01% on the tomato seed germination, plants’ productivity (which is 33.9% higher) and the biochemical characteristics of the tomato fruit. It was elucidated, for the first time, the inhibitory effect of genistifolioside on the development of Alternaria alternata pathogenic fungi, affecting the vegetable crops; the 0.1% aqueous solution of genistifoliosides has the diameter of the fungi zone of inhibition 5.8 times bigger in comparison to the control sample and 4 times bigger in comparison to the certificated biopreparation. The purified extract of genistifoliosides exhibits properties of plant growth regulator as well as fungicidal properties and can be used in ecological agriculture.