Growth Response and Brix Content of Sorghum <i>(Sorghum bicolor L. Moench)</i> Under Application of Biochar-Based Fertilizer on Sandy Soils in the Tropical Semi-Arid Areas of Northern Lombok, Indonesia

Abstract One of the important cereal crops in the world is sorghum. It produces seeds for food and stems that can be squeezed to produce sap for bioethanol, and the rest of the stem pulp is used for animal feed. This study aims to evaluate the growth response and brix content of sorghum after applying biochar combined with cattle manure. The field trial was conducted during the dry season commencing from April to July 2024 at the field station of dry land in North Lombok Regency, especially in Akar-Akar Village, Bayan District. The experiment was set up using a Randomized Block Design (RBD) with six treatments tested: without biochar (P0); Biochar 20 tons ha-1 (P1); Cattle manure 20 tons ha-1 (P2); NPK 200 kg ha-1 (P3); Biochar 20 tons ha-1 + Cattle manure 20 tons ha-1 (P4); Biochar 20 tons ha-1 + Cattle manure 20 tons ha-1 + NPK 200 kg ha-1 (P5). These treatments were repeated three times. The study showed that applying biochar-based organic fertilizer improved growth performance and brix content of sorghum compared to control. The highest total top dry weight per plant (129,01) was obtained at the treatment of P5. The application of biochar combined with cattle manure and NPK improves brix content. Regardless of the type of treatment, the brix content of sorghum measured at 90 dan 105 days after sowing (DAS) was consistently higher than measured at 75 DAS. The highest brix content measured at 105 DAS was obtained at treatments of P2, P4, and P5 (21%).