Abstract
This research aims to determine the appropriate concentrations of nitrogen, phosphorus, and potassium (NPK) in liquid organic fertilizer (LOF) and to determine the appropriate dose of NPK and LOF concentrations for the growth and yield of rice plants. The research was conducted in Mertajati Village, Sausu Subdistrict, Parigi Moutong Regency, Indonesia, from August to December 2019. The study used a two-factor randomized block design (RBD). The first factor is the dose of NPK, which consists of three levels, i.e., NPK 200 kg/ha-1, NPK 400 kg/ha-1, and NPK 600 kg/ha-1. The second factor is the concentration of LOF, which also consists of three concentration levels, i.e., without LOF, 2.5% LOF, and 5.0% LOF. The results revealed that the effects of LOF addition were the same for each dose of NPK and increasing the dose of NPK required an increase in the concentration of LOF. A dose of 400 kg ha-1 NPK fertilizer resulted in better growth and a higher yield, indicated by taller plants, higher panicles (19.53 panicles), and higher dry grain production (7.69 ton/ha-1). The application of 2.5% liquid organic fertilizer resulted in better growth and a higher yield, indicated by taller plants, a higher number of tillers, faster flowering, more panicles per clump (19.72 panicles/clump-1), a higher number of grains per panicle, a higher pithy grain weight (30.26 grams/1000 grains), and higher yields (7.79 tons/ha-1).