Optimisation of Plant Mineral Nutrition, Growth Stimulation and Yield Enhancement Through the Use of a Bio Formulation Based on Phosphate Solubilising Bacteria

The aim of this study was to evaluate the agronomic and fodder efficiency of various fertilisation treatments in relation to their effects on plant growth, chemical composition, and soil properties. The study evaluated the effectiveness of a bio-formulation based on Phosphate-Solubilising Bacteria (PSB) in combination with mineral fertiliser (N60P90 + N30) in enhancing the productivity of forage crops and improving the agrochemical properties of soil. Under field conditions, Mohar, Sudan grass, and barley were investigated. Morphometric parameters, yield, fodder quality, and the dynamics of soil characteristics were determined. Data were statistically analysed using one-way analysis of variance (ANOVA) followed by the Least Significant Difference (LSD) test at p<0.05, and results are presented as mean ± Standard Error (SE). The highest values for plant height, number of stems and spikes, as well as spike length, were recorded under the combined application of mineral fertiliser and PSB. In Sudan grass, height reached 36.4 cm, the number of stems 10, spikes 9, spike length 43.5 cm, which exceeded the control by 32.8% and 7.1 cm, respectively. In barley, under the same treatment, green mass yield reached 16.2 t ha⁻¹, dry matter yield 41.2 t ha⁻¹, representing an increase of 7.8% compared with the control. In Mohar, high crude protein content (19.4%), digestible protein (114.7 g kg⁻¹), metabolizable energy (8.15 MJ kg⁻¹) and feed units (0.82 FU) were recorded. From an agrochemical perspective, the content of available phosphorus increased to 62 mg kg⁻¹, potassium to 140 mg kg⁻¹, and humus to 0.75%. At the same time, total salt content decreased to 1.19%, and sodium concentration was reduced by 2.1 mEq 100 g⁻¹. The practical value of this work lies in substantiating the feasibility of integrating PSB into mineral nutrition systems to enhance productivity and sustainability in forage crop production.