Effect of Formulation and Concentration of Liquid Organic Fertilizer from Enriched Fish Waste Trichoderma on the Growth and Yield of Tomato Plants (Solanum Lycopersicum)

Tomato production in Bali Province in 2023 reached 5,218 tons, but decreased by 16.04% in 2024 to 4,381 tons. Declining productivity is often associated with nutrient limitations in the soil. This study aims to evaluate the formulation and concentration of liquid organic fertilizer (POC) made from fish waste enriched with Trichoderma sp. on the growth and yield of tomato plants. The experiment used a factorial randomized block design (RAK) with two factors, namely formulation (J0: control, J1: POC + Trichoderma, J2: POC without Trichoderma) and concentration (P0: control, P1: 5 ml/L, P2: 10 ml/L, P3: 15 ml/L). The variables observed included plant height, leaf chlorophyll content (SPAD), number of productive branches, number of fruits per plant, fruit diameter, and fruit weight per plant. The results showed that fish waste POC enriched with Trichoderma increased tomato growth and yield compared to other treatments. A concentration of 15 ml/L had the most significant effect on plant height, number of productive branches, chlorophyll content, and fruit yield. The best interaction was obtained with the combination of POC + Trichoderma at a concentration of 15 ml/L, which resulted in the highest plant growth, fruit diameter, and fruit weight.