Impacts of gyttja application on morphological, physiological, and biochemical parameters in soybean and soil

The use of organic amendments in sustainable agriculture has gained increasing attention to improve soil fertility and plant productivity under challenging environmental conditions. This study evaluated the effects of different gyttja concentrations (1.5%, 3.0%, and 4.5%) on plant growth, physiological responses, antioxidant enzyme activities, and soil biochemical properties in soybean (Glycine max L.) under semi-arid conditions. A pot experiment with three replications was conducted in a completely randomized design. Gyttja significantly enhanced shoot height (28%), root length (24%), and biomass production (22%) compared to the control, particularly at 3.0% and 4.5% concentrations. Physiological traits such as SPAD readings (19%) and stomatal conductance (17%) improved, indicating increased photosynthetic efficiency. Oxidative stress indicators decreased at moderate doses, with MDA reduced by 26% and H₂O₂ by 21% at 3.0%, while the 4.5% application increased some stress markers (MDA + 18%) alongside certain growth and enzymatic parameters, suggesting a dual effect. Soil enzyme activities such as urease (29%), dehydrogenase (27%), and catalase (21%) increased, accompanied by slight rises in pH (3%) and electrical conductivity (6%), reflecting enhanced microbial activity and nutrient cycling. These findings demonstrate gyttja's potential as a multifunctional organic amendment that supports plant vigor and improves soil health in semi-arid environments. However, high application rates may induce stress, highlighting the importance of dose optimization. Gyttja can be considered a promising component of sustainable agricultural systems, particularly for nutrient-poor soils, but further field-scale research is needed to confirm its long-term effectiveness. This study provides novel evidence on the multifunctional role of gyttja in enhancing plant growth and soil health under semi-arid conditions, offering valuable insights for its integration into sustainable agricultural practices across nutrient-poor regions.Trial RegistrationThis study does not involve any human participants and is therefore not a clinical trial.