The Effect of a Combination of N, P, K and Biochar-Silica Fertilizers On CEC, C-organic, N, P, K Content of Plant and Yield of Rice on Inceptisols Jatinangor, Indonesia

Inceptisols have enormous potential for cultivating lowland rice because of their wide distribution in Indonesia, but low fertility is one of the problems with Inceptisols. The experiment aims to determine the effect of a combination of N, P, K, and biochar-silica fertilizers on CEC, C-organic, N, P, K content of plant, and rice yields and to obtain a treatment combination that gives the best lowland rice yields on Inceptisols. The experiment was carried out from August to November 2024 using experimental plots as experimental units and arranged in a Randomized Completely Block Design (RCBD) consisting of 10 treatments and three replications, namely 3 treatments with a combination dose of 0% N, P, K and biochar-silica, 3 treatment with a dose of 50% N, P, K and biochar-silica, 3 treatments with a dose of 100% N, P, K and biochar-silica, and 1 control treatment. The experimental results showed that the combination of N, P, K, and biochar-silica fertilizers could influence CEC, organic C, P, K element content in plants, and rice yield, but did not have a significant effect on plant N content. Treatment N, P, K (175 kg ha-1 Urea, 25 kg ha-1 SP-36, and 25 kg ha-1 KCl) and dose of biochar (2.5 ton ha-1) + silica 320 kg ha-1 is the treatment with the best dose in increasing the yield of harvested dry grain (GKP) for lowland rice, namely 3.37 kg plot-1.