A comparative assessment of potassium mineralization from waste mica by application of potassium solubilizers and FYM in alluvial and black soils

Abstract Potassium (K) deficiency poses a major challenge to sustainable agriculture, affecting crop productivity and soil fertility. Conventional potassium fertilizers are costly and contribute to environmental degradation such as eutrophication and resource depletion, highlighting the need for sustainable alternatives. Mica, a potassium-bearing mineral, remains underutilized due to its slow-release nature. This study investigates whether potassium solubilizers, specifically Enterobacter wuhouensis , can enhance potassium availability from mica in alluvial and black soils. A 60-day incubation experiment was conducted using a completely randomized design (CRD) with 9 treatments and 3 replications, varying the proportions of mica, farmyard manure (FYM), and potassium solubilizers. Results showed that the addition of potassium solubilizers and FYM significantly improved K solubilization compared to mica alone, with the highest effects observed when potassium solubilizers were combined with 75% mica and 25% FYM. This combination led to the greatest increases in available potassium, reaching 322.67 kg ha⁻¹ in alluvial soil and 398.00 kg ha⁻¹ in black soil at 60 days. Microbial activity and dehydrogenase enzyme levels were also significantly improved. These findings suggest that integrating potassium solubilizers with mica and FYM provides a viable, eco-friendly, and low-cost approach to enhance soil potassium availability and promote sustainable nutrient management.