Environmental Research, vol.243, 2024 (SCI-Expanded)
The aim of this study is to investigate the effects of vermicompost on the biological and microbial properties of lettuce rhizosphere in an agricultural field in Samsun, Turkey. The experiment was conducted in a completely randomised design (CRD) and included four vermicompost dosages (0%, 1%, 2%, and 4%) and two application methods (with and without plants). Batavia lettuce was selected as the test plant due to its sensitivity to environmental conditions and nutrient deficiencies. The study evaluated the changes in organic matter (OM), pH, electrical conductivity (EC), carbon dioxide (CO2), dehydrogenase activity (DHA), microbial biomass carbon (MBC), and catalase activity (CA) in the rhizosphere of lettuce plants treated with different vermicompost levels (0%, 1%, 2%, and 4%). The findings showed that vermicompost application significantly increased chlorophyll content in lettuce plants, with the highest content observed in plants treated with V1 compared to the control. Different vermicompost concentrations also influenced chlorophyll b and total chlorophyll levels, with positive effects observed at lower concentrations than the control. Plant height and fresh weight were highest in plants treated with V2, indicating the positive impact of vermicompost on plant growth. Additionally, vermicompost application increased plant dry weight and improved soil properties such as pH, organic matter content, and microbial activity. The findings showed that vermicompost increased the rhizosphere's microbial biomass and metabolic activity, which can be beneficial for plant growth and disease suppression. The study highlights the importance of understanding the effects of organic amendments on soil properties and the microbial community in the rhizosphere, which can contribute to sustainable agricultural practices. Overall, the results suggest that vermicompost can be used as an effective organic amendment for enhancing plant growth and improving soil properties in agricultural fields. Moreover, based on the data, it can be suggested that a dose between 1% and 2% vermicompost is beneficial for the overall growth of plants.