Russia is one of the largest cereal grain exporters in the world, churning out 34,3 million tons of export grain (wheat, barley and oats) in 2021. Plant infectious pathogens continue to be among the main factors in yield loss in the field and are a danger to the grain exporting industry's ability to expand internationally. This is primarily due to phytosanitary restrictions imposed by nations that monitor the presence and absence of certain phytopathogens in imported goods. Phytosanitary measures prevent the spread of plant pathogens, thus cutting the cost of dealing with them, once the pathogens invade new agricultural regions. This paper is devoted to the detection and identification of bacteria in samples of grain crops of three regions in The Republic of Crimea. The objects of the study were bacterial isolates from plant samples particularly wheat, oats, barley and triticale. The study was conducted in 2021. The identification of the isolates was carried out by sequencing a section 16–23S of the rRNA amplified by PCR with 8UA/519B, 27f/907r and PSf/PSr primers. Nucleotide sequences were deciphered using the Bio Edit program and compared with sequences placed in GenBank (https://blast.ncbi.nlm.nih. gov). The result of identification was considered an organism with maximum similarity. As a result, 38 samples of grain crops were collected, 95 bacterial colonies were isolated, of which 68 were identified to genus level and 22 were identified to species level. Some of the phytopathogens identified include: Agrococcus jenensis, Pseudomonas sp. and Curtobacterium sp. Some of the bacteria identified are beneficial like Ochrobactrum sp. Erwinia sp. and Pantoea sp. had a frequency of 28.95%, with Pantoea agglomerans having a frequency of 18.42%. Ochrobactrum sp. had a frequency of 10.53%. Enterococcus mundtii an frequency of 5.26%. Information about the species composition of bacteria on grain crops can be used to determine the spread of bacteria and their diagnosis and for bioinformatic analysis of genomes in search of species-specific genetic markers.

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