Effect of Liquid Organic Fertilizer and Inorganic Fertilizer on Soil Nutrient Content (N, P, and K) in Lowland Rice (Oryza sativa L.) Cultivar Ciherang

The decline in soil nutrient availability caused by long-term inorganic fertilizer use has prompted the adoption of organic-based alternatives in paddy systems. This study aimed to evaluate the effects of liquid organic fertilizer (LOF) and its combination with inorganic NPK fertilizer on soil nutrient content—specifically total nitrogen (N), available phosphorus (P), and exchangeable potassium (K)—in lowland rice (Oryza sativa L. cv. Ciherang). The experiment was conducted using a randomized complete block design (RCBD) with 11 treatments: nine LOF dose variations, one recommended dose of NPK, and one unfertilized control, replicated three times. The results showed that both LOF and NPK had significant effects on soil nutrient status, with the combined application producing superior outcomes compared to single inputs. Among all treatments, the full combination of LOF and NPK (treatment H) yielded the highest nutrient concentrations: 0.30% total N, 35.65 mg/100g P₂O₅, and 36.14 mg/100g K₂O. These findings indicate that integrated fertilization enhances nutrient availability more effectively than individual applications, supporting the potential of LOF as a complementary component in sustainable nutrient management for paddy rice cultivation.