Abstract. Monitoring of forest and meadow phytocenoses in the Greater Caucasus regions was
conducted. The phytocenotic association of Lapsana communis, Leontodon hispidus, Pojarkovia
pojarkovae, Tanacetum coccineum, Centaurea phrygia subsp. salicifolia, Aconitum nasutum and
Lomelosia caucasica, as well as the species composition and tiering of accompanying species were
studied. These species are components of forest and meadow phytocenoses and actively participate
in the formation of various plant communities. A total of 107 species belonging to 88 genera and
41 families were registered in forest areas. Among from them 16 are trees, 12 are shrubs and 79
are herbaceous plants. In meadow phytocenoses 101 species from 83 genera and 32 families were
noted. Herbaceous plants were the most represented (95 species), while trees (2), shrubs (3) and
sub-shrubs (1) were the least represented.Most of the studied species are representatives of the
Asteraceae family (10 in forest and 22 in meadow phytocenoses), Lamiaceae (9 in each phytocenosis),
Apiaceae (3 and 7, respectively), Fabaceae (7 and 6), Rosaceae (5 and 6) and Orchidaceae (5 species
each). Additionally, the ontogenetic and demographic structure of coenopopulations (CP) of two
Caucasus endemics - Pojarkovia pojarkovae and Tanacetum coccineum was studied. Four CPs of
each species were identified and studied in different areas. The study revealed that all CPs were
normal, but some were incompleted due to the absence of subsenile and senile individuals. Based
on the Δ-ω indices, CP 1 of P.pojarkovae is a transitional type, while the remaining CPs are young.
For T. coccineum CP 1-2 are transitional, CP 3 is maturing, and CP 4 is young. The study of the
antimicrobial activity of aqueous-alcoholic and methanol extracts of the studied species was also
examined. The extracts of Centaurea phrygia subsp. salicifolia flowers, Leontodon hispidus roots,
Aconitum nasutum leaves and Lapsana communis aerial parts showed more effective effect on
test cultures of Staphylococcus aureus (MSSA). Methicillin-resistant Staphylococcus aureus (MRSA),
Bacillus anthracoides, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and
Candida albicans.