Alternatives to nutrient solution for lettuce (Lactuca sativa L.) production under passive hydroponics system

Growing of lettuce using hydroponics system is increasing nowadays. However, the production is limited by the availability and high cost of inorganic nutrient solution. Alternatives to inorganic nutrient solutions such as organic-based solutions were tested in this study under passive hydroponics system. The following treatments were evaluated: 55% fish amino acid (FAA), 100% FAA, 50% fermented plant juice (FPJ), 50% vermicompost tea (VCT), 100% VCT, recommended rate of inorganic nutrient solutions (INS) and water (control). Lettuce was grown for 30 days in Styrofoam boxes maintained with 2 cm depth of nutrient solutions. VCT at 50% and 100% concentrations proved to be a good alternative nutrient solution for lettuce production under passive hydroponics system since the chlorophyll content, number of leaves, width of leaves, plant height and weight were comparable with the plants in inorganic nutrient solution. Root length and total soluble solid had no significant differences among the VCT treatments, INS and water. The use of FAA (50% and 100%) and FPJ (50% and 100%) on the other hand, produced a retarded growth and early senescence of lettuce plant.