DYNAMICS OF SOIL BACTERIAL COMMUNITIES UNDER WINTER WHEAT IN THE NORTH-EAST PART OF ROMANIA

Agricultural soil microbial communities are influenced by a multitude of factors, including seasonality and local environmental conditions, management practices and their interaction, and cultivated species. Seasonality can result in variations in temperature, precipitation, soil moisture, and solar radiation, all of which drive rates of soil microbial metabolism and respiration, as well as taxonomic composition. Agricultural crop species can significantly impact the soil microbial population through the release of root exudates. Root exudates are a diverse array of organic compounds that are actively secreted by plant roots into the surrounding soil. These compounds include sugars, organic acids, amino acids, vitamins, enzymes, and other secondary metabolites. Root exudates serve various functions, including providing a carbon source for soil microorganisms, facilitating nutrient uptake by plants, and mediating plant-microbe interactions. This study investigates the dynamics in bacterial communities within the rhizosphere of winter wheat across different growth stages and geographical regions in north-eastern Romania. Soil samples were collected from two locations in Iasi County, one location in Botosani County, one location in Vaslui County, and one location in Galati County. Soil sampling occurred three times during the winter wheat growing season: in the fall of 2022, in April 2023, and in May 2023, covering three phenological stages (emergence, stem elongation, and flowering). The results obtained indicated differences between the wheat crop's phenophase and between locations; however, statistical analysis of the data demonstrated that these differences were not statistically significant.