Fedorova Ekaterina Dmitrievna

The article presents the results of the research of the prokaryotic complex associated with plants in blackalder-meadowsweeteutrophic swamp (Zapadnodvinskiy District, Tver Region). The phylloplane (leaves, stems), rhizoplane (roots), and rhizosphere soil of six plants, namely Calla palūstris L., Filipendula ulmaria (L.) Maxim., Carex cespitosa L., Urtica dioica L., Athyrium filix-femina (L.) Roth ex Mert.and Scirpus sylvaticus L., were analyzed. The abundance of unicellular and mycelial bacteria in plant and soil substrates was determined by luminescent microscopy and culture method. The taxonomic composition of cultured bacteria was assessed on the basis of phenotypic characteristics and the results of 16S rRNA nucleotide sequence analysis. It was found that the dimensionless universal characteristic of prokaryotic communities — the K index (the ratio of bacteria counts based on microscopy and culture data) —and the alpha diversity index (the Shannon index)— increase in the order phylloplan<rhizoplan< rhizosphere soil. Representatives of 4 phyla, 23 genera, and 63 species of cultivated bacteria, 27 of which are mycelial. were isolated and diagnosed from the analyzed substrates. It was determined that Carexmicroloci were characterized by maximum abundance and diversity of bacteria. Filipendulamicroloci are promising targets for the isolation of streptomycetes with antagonistic potential against phytopathogenic fungi that cause various diseases in agricultural plants. It was shown that rhizosphere soil under plants in blackalder-meadowsweeteutrophic swamps is a substrate for the isolation of bacteria of the genus Stenotrophomonas, which are used as effective bioinoculants to stimulate plant growth and as microbiological agents for biocontrol.