Diversity of phosphate-solubilizing, nitrogen-fixing and pathogenic bacteria in soils of cultivated fields of the Sverdlovsk region

Relevance. The availability of organic substances and environmental pathogenicity are key factors in plant growth. Phosphate solubilizing bacteria convert phosphate to an available form, while nitrogen fixing bacteria provide nitrogen for plants. Bacterial infections can weaken plants, causing them to die or lose their crops. Modern sequencing technologies have accelerated the study of human microbial diversity. The aim of this study was to assess the presence of phosphate solubilizing and nitrogen fixing bacteria, as well as pathogenic bacteria affecting potatoes in the cultivated areas of the Sverdlovsk region. Methods. This article examines the characteristics of the soils in the Sverdlovsk area, their mineral and organic composition, and bacterial diversity. Studies were conducted on sodpodzolic soils where humus content, acidity levels, and nutrient content were measured. Analysis of the microbiological composition of the soil included sequencing and filtration of 16S rRNA data. Results. It was found that bacteria involved in phosphate mobilization and nitrogen fixation make up a significant portion of the microbial community, with more than 12% accounted for by these groups. The distribution of these bacteria across fields showed no significant difference in relative abundance or species composition. Additionally, no significant correlation was found between bacterial species richness and mineral composition of soil. However, correlation analysis of relative abundances of genera Agrobacterium, Rhizobium, Bradyrhizobium, Phyllobacteri, Arthrobater and Phylobacter revealed a significant relationship between these genera and soil acidity and total and easily hydrolysable nitrogen content. Qualitative analysis also revealed the presence of pathogenic bacteria causing potato bacteriosis such as Ralstonia solanacearu, Pectobacterium carotovaru, Liberibacter crecens, Streptomyces spp.