Fermented lettuce waste as an organic nutritional supplement of synthetic fertilizer in hydroponic production of Archivel lettuce

Resíduos de alface fermentados como suplemento nutricional orgânico ao fertilizante sintético na produção hidropônica de alface Archivel

ABSTRACT

Lettuce productivity grown hydroponically increases, but the plant quality is lower than conventional because of the absence of organic compounds. Lettuce waste is an organic material contributing 15-20% of the total weight of the plant and has the potential to be used as liquid organic fertilizer (LF). The objective of the study was to evaluate the effect of lettuce waste as an organic nutritional supplement on lettuce growth and development in a hydroponic system. Different quantities of lettuce waste were fermented in liquid-enriched oxygenation nanobubbles for 22 days. LF at 0.5-2% was incorporated into the AB-mix fertilizer, and their effect on the morphophysiological characters of Archivel lettuce was evaluated. Organic supplementation in synthetic fertilizer effectively increased Archivel lettuce growth in hydroponic cultivation. Organic fertilizer at 1.5% supplementation in AB-mic mixtures increased biological fresh weight by 28.03% over AB-mix, representing by plant height, canopy diameter, leaf number, and area, the quantity of photosynthetic pigments, and vitamin C in leaves improvement. Lettuce waste has the potential to be utilized in the organic hydroponics of lettuce; nevertheless, further investigation is needed to limit the unfavorable excess of ionic presentation in oxygenation nanobubbles fermented biomass.

Index terms:
Romaine; bio-based nutrition; crop-residue; soilless; plant-food