Evaluation of total phenols in alfalfa (Medicago sativa L.) collected from different localities in Republic of Macedonia

Phenols are secondary biomolecules, which in their structure contain an aromatic ring attached to one or more substituents, such as flavonoids, which are one of the largest class plant phenols. Phenolic compounds participate in biochemical processes that are important for the protection of plants against infections caused by fungi and viruses, mechanical damage, regulation of metabolism, and more. Phenolic compounds are oxidized by phenol oxidases to quinones, by releasing hydrogen and thus directly participating in the exchange of matter. The intensity of the biosynthesis of phenolic compounds increases after plant infection with pathogenic microorganisms. Therefore, the amount of total phenolic in plants can be used as biochemical parameter and indicator in the selection of plants for resistance to fungi, bacteria and viruses. Phenolic compounds are intensively synthesized in mechanical damage to plants, whereby they build protective film with active condensation in damaged areas. In this way they prevent cell wall degradation in infections caused by the necrotropic pathogens that destroy the cells in order to build their colonies on the dead tissues. This paper presents the results of the research on the determination of the total phenols determined in three regions of the Republic of Macedonia in a total of 20 different locations. The content of the total phenols in the dry plant material of alfalfa in three mowings was determined by routine method in Folin-Ciocalteu (1927). The quantitative determination of total phenols in the plant ethanol extract was performed spectrophotometrically at a wavelength of 765nm. Key words: Lucern mowings, spectrophotometry, phenolic compounds, forage cro