Effect of NPK, and Si Fertilizers on Exchangeable Potassium, K Uptake and Growth of Black Rice (Oryza sativa L. indica) on UltisolsAnni Yuniarti, Eso Solihin, Alifia Syifa Alzena Wibowo and Saedi BawanaE3S Web of Conf., 444 (2023) 04027DOI: https://doi.org/10.1051/e3sconf/202344404027