Pemanfaatan biochar sekam dan kompos jerami padi terhadap pertumbuhan dan produksi padi (Oryza sativa) pada tanah ordo Ultisol

Abstract

This study aimed (1) to determine the effects of rice husk biochar and rice straw compost on the growth and production of rice (Oryza sativa L.) and (2) to evaluate their ability to supply nutrients to Ultisol soil. The research was conducted from February to July 2018 in Sungai Abang Village, Lubuk Alung, Padang Pariaman. A randomized block design was applied with five treatments: 0% rice husk biochar + 0% rice straw compost; 100% biochar + 0% compost; 75% biochar + 25% compost; 50% biochar + 50% compost; and 25% biochar + 75% compost. Observations included soil analyses before treatment application, after incubation, and at the end of the experiment. Soil parameters comprised pH, total nitrogen (N), available phosphorus (P), exchangeable potassium (K), calcium (Ca), and magnesium (Mg), and sulfur (S). Plant observations included plant height, number of productive tillers, total number of tillers, and grain yield per hectare during the experimental period. The results showed that rice husk biochar and rice straw compost affected rice growth and production. The treatment consisting of 75% rice husk biochar and 25% rice straw compost produced 29 productive tillers and a grain yield of 8.238 tons per hectare. In addition, applying rice husk biochar and rice straw compost improved nutrient availability in Ultisol, as indicated by increases in soil pH and the measured levels of N, P, K, Ca, Mg, and S. These findings indicate that combining these amendments can support rice production while improving soil fertility under the conditions of this study.