QUALITY OF SHALLOT WASTE LIQUID ORGANIC FERTILIZERAND ITS EFFECT ON RED LETTUCE

Converting organic waste into liquid organic fertilizer (LOF) can reduce reliance on inorganic fertilizers and improve soil quality and the productivity of leafy vegetables, including red lettuce. The study aimed to 1) determine the chemical and microbiological properties of LOF from shallot waste (LOF-Shallot) and 2) analyze the growth and yield of red lettuce cv Arista after applying various concentrations of LOF-Shallot. The LOF-Shallot was produced using a fermentation method enriched with decomposer microbes. The field experiment was set up using a Randomized Block Design, with five LOF-Shallot concentrations (0, 30, 60, 90, and 120%), then applied 4 times every 7-day period. The research was conducted at the Chemistry Laboratory of UICM, Bandung City, and the experimental field in Cimenyan village, Bandung Regency, from June to September 2024 The results of the LOF-Shallot waste analysis contained total N 0.12%, P 0.16%, K 0.07%, Cu 3.14 ppm, Fe 151.77 ppm, and Zn 492.4 ppm. Beneficial soil microbes such as Azotobacter sp., Bacillus sp., and phosphate-solubilizing bacteria at 107–108 CFU mL-1 were detected in the LOF-Shallot waste. The total bacterial population in the LOF-Shallot was about 108 CFU mL-1, while the total fungal count was low, fewer than 102 CFU mL-1. The results of field experiments showed that the higher concentration of LOF-Shallot applied (up to 90%), the greater the effect on all observed variables. The application of 90% LOF-Shallot concentration had the best effect on shoot height, leaf count, and shoot fresh weight.