The investigation studied the influence of biological preparations based on bacterial strains of Bacillus mojavensis and Bacillus amyloliquefaciens on the quantitative composition of the plants and soil microbiomeduring the cultivation of spring wheat Ulyanovskaya105 variety. Some ability of these strains to pass from the treated seeds into the interior of plants and into the soil on the early stages of wheat development was also considered. Ulyanovskaya 105 wheat variety was cultivated in the Laishevsky district of the Republic of Tatarstan during the 2020 and 2021 summer periods. During the two growing seasons, different weather conditions were observed.The strains used for seed treatment are endophytic microorganisms isolated from the tomato (Bacillus amyloliquefaciens) and spring wheat seeds (Bacillus mojavensis).At the early stages of plant development, the analysis of the bacterial microbiota, both of the plants themselves and of the soil in which they were cultivated, was carried out.According to the results of the study, we noted that the use of these preparations, in general, increases the number of bacteria of soil and plants. The ability of the Bacillus mojavensis strain to move into the aerial part of the plant, and the ability of the Bacillus amyloliquefaciens strain to move into the plant roots and soil was revealed. The data obtained for two summer seasons of wheat cultivation: 2020 and 2021 showed some coherence between the effect of biological products on the microbiome and weather conditions.In addition, the studies noted that the treatment of plants with a strain of Bacillus mojavensis contributes to the preservation of the microbiome, both plants and soil in adverse weather conditions.