YIELD PERFORMANCE OF THREE LETTUCE VARIETIES GROWN UNDER DIFFERENT LED LIGHT SPECTRUM

Abstract

This present study was conducted to evaluate the yield performance of lettuce under led light spectrum. The experiment was comprised of two factors, viz., three light spectrums [WhC - White Light (Control), Wr-Florescent Light (known as warn light), Rb- R4:B1] and three lettuce varieties [BL1- BARI Lettuce-1, RL- Red Lettuce, IcB- Ice Berg Lettuce] grown in deep water culture with a floating raft system using hydroponics nutrient solutions. Plants were hydroponically cultured with a 16-h photoperiod at 20/18 C (day/night), 75-80% relative humidity, and 100 mol m

photon flux density (PFD) under Rb LED, Warm (Wr) LED, and White (WhC) inside growth chambers for 42 days. The marketable sensory characteristics (crispness, sweetness, sourness, bitterness, and appearance) of fresh plants were also evaluated. The shoot and root fresh and dry weights as well as the acceptance of the plants treated with Rb were higher with IcB than those of plants treated with WhC and Wr light. Anthocyanin and antioxidant% were significantly higher in plants grown under WhCRL (9.99) and (60.54%) treatments, respectively, than in those grown under Rb treatment, whereas 0brix and Vitamin C content were higher in plants grown under Wr (6.70) and Rb (1.20) treatments, respectively, for Ice Berg Lettuce. RbIcB (0.16kg, 0.80kg, 47.35 ton) outperformed RbRL (0.14kg, 0.73kg, 43.23 ton) and WrBL1 (0.14kg, 0.73kg, 43.17 ton) in terms of fresh weight plant ii -1 (kg), yield pot (kg), and yield ha -1 (ton). The treatment (RbIcB) Rb light and Ice berg varieties had the best significant positive effect on growth, yield contributing parameters, and yield and quality parameters of lettuce and resulted in the highest fresh weight plant (0.16 kg) and total yield (47.35 t ha -1 ) compared to all other treatments. Precise control of irradiance and wavelength may hold promise for improving the economic efficiency, -1 -1 −2 s −1 quality, and nutritional potential of vegetables grown in controlled environments.