Vol. 9, Special Issue 8, Part B (2025)

Using factorial combination of nitrogen (poultry litter, greengram flour, groundnut cake), phosphorus (rock phosphate, PROM, bone meal) and potassium-rich (potassium humate, wood ash, pressmud) agro-residues, a total of 27 treatments were developed along with two controls (absolute and chemical). Probiotic strains including Lactobacillus spp. and Saccharomyces spp (extracted from milk and bread) were subjected to co-fermentation with Azospirillum, phosphate-solubilizing bacteria (PSB), and potassium-mobilizing bacteria under aerobic conditions for 30 days at optimum temperature of 30 ± 2 °C and pH 6.5-7.5. The formulation containing groundnut cake + rock phosphate + potassium humate recorded the highest NPK content of 15% along with the presence of important metabolites like indole-3-acetic acid (IAA), gibberellic acid, cellulase and phosphatase.

Through a three-month rice cycle of field evaluation, the treatment (T₂₁) containing 50% organic NPK liquid fertilizer along with 50% RDF observed to significantly enhanced the height of the plant (90.6 cm), tillering (15 tillers/plant) and grains (125 grains/panicle) as compared to control and chemical fertilizer alone. Using agro-waste will definitely valorise crop production in a sustainable way by reducing the dependency on chemical inputs.