Utilizing glauconite extracts to enhance soil health and sugar beet (Beta Vulgaris L.) performance in salt-affected soil

Soil salinity remains a critical constraint to sustainable agricultural production and long-term soil resource management. A field investigation was conducted over two consecutive growing seasons (2022/2023 and 2023/2024) to evaluate the potential of glauconite-derived potassium amendments for improving soil health and enhancing sugar beet (Beta vulgaris L.) performance under saline soil conditions. Treatments included conventional potassium sulfate (K₂SO₄), raw glauconite powder (G), and foliar applications of glauconite extracts prepared with EDTA (GE), nitric acid (GN), and fulvic acid (GF), each applied at two concentrations (20 and 40 mL L ⁻ ¹). Among the tested treatments, GE2 and GF2 produced the most substantial improvements in soil quality, with GF2 reducing soil electrical conductivity by 35.11% and exchangeable sodium percentage by 23.33%, while increasing organic matter content and available nutrients. Soil biological indicators also responded positively, with GF2 enhancing dehydrogenase, urease, and phosphatase activities by 7.21%, 16.43%, and 48.60%, respectively. Correspondingly, GF2 achieved the highest increases in root yield (67.79%), shoot biomass (107.34%), and sugar yield (92.11%). Multivariate analyses (PCA and RDA) confirmed strong linkages between sugar yield and key soil variables, particularly available potassium, enzymatic activities, and microbial biomass. These results demonstrate that tailored glauconite-based foliar formulations-especially fulvic and EDTA extracts at higher concentrations-can serve as environmentally sound and agronomically effective measures for improving soil quality, restoring saline-affected lands, and enhancing sustainable crop productivity within the broader framework of soil and water conservation.