Effects of local micro-organisms (LMO) biodecomposer on compost quality and the growth of cocoa seedlings (Theobroma cacao L.)

Abstract

This study aimed to evaluate the effect of different concentrations of local micro-organisms (LMO) biodecomposer on compost quality and the growth of cocoa seedlings (Theobroma cacao L.). The experiment was conducted from October 2024 to February 2025 in South Sulawesi, Indonesia, using a Randomized Block Design (RBD) with four treatments: M0 (control), M1 (20 mL/L), M2(30 mL/L), and M3 (40 mL/L). Compost quality was analyzed based on pH, organic C, total N, C/N ratio, P2O5, K, and cation exchange capacity (CEC), while seedling growth parameters included plant height, stem diameter, number of leaves, leaf area, and root length. The results showed that the application of 40 mL/L LMO (M3) produced the best compost quality, with pH 7.25, organic C 20.14%, N 1.11%, C/N ratio 18, and P2O5 0.94%, with the highest CEC (35.24 cmol kg−1) was observed in M2. Furthermore, M3 significantly improved cocoa seddling growth, resulting in the highest plant height (51.3 cm), stem diameter (15.1 mm), number of leaves (25.0), leaf area (310.5 cm2), and root length (39.6 cm). In conclusion, LMO biodecomposer at mL/L is the most effective concentration for improving compost quality and promoting optimal growth of cocoa seedlings.