The Response of Dongan Cultivar to the Application of NPK Fertilizer and Liquid Organic Fertilizer (POC)

Abstract Fertilization technology is one of the methods to enhance the growth and yield of local upland rice, requiring precise dosages to achieve optimal growth and production while minimizing environmental impacts. This study aims to determine the appropriate dosages of NPK fertilizer and liquid organic fertilizer (POC) for the growth and yield of local upland rice cultivars. The research was conducted on agricultural land in Tamarenja Village (Dusun III Kalama), Sindue Subdistrict, Donggala Regency, Central Sulawesi Province, located at 00°26’51.4” S and 119°49’50.5” E, with an altitude of 230 meters above sea level. The study was carried out from November 2020 to March 2021. A factorial randomized block design (RBD) was employed, comprising two factors: the first factor was four levels of NPK fertilizer doses (N0 = no NPK fertilizer, N1 = 100 kg/ha, N2 = 200 kg/ha, and N3 = 300 kg/ha), and the second factor was three concentrations of POC (P0 = no POC, P1 = 1% POC, and P2 = 2% POC), with three replications, resulting in 36 experimental plots. The results revealed that applying 100 kg/ha of NPK without liquid fertilizer significantly improved the number of tillers, productive tillers, panicle length, the number of grains per panicle, and overall production. Independently, the application of 200 kg/ha of NPK enhanced plant height, leaf count, leaf length, and accelerated flowering and harvesting time. Additionally, the independent use of 2% liquid organic fertilizer increased leaf count, leaf length, and 1,000-grain weight in the local upland rice cultivar.