Growth and Quality of Hydroponic Cultivated Spinach (Spinacia oleracea L.) Affected by the Light Intensity of Red and Blue LEDs

This study aimed to evaluate the effect of four light intensities (90, 140, 190 and 240 µmol m-2 s-1) provided by red-blue LED (spectrum ratio: R660/B450 = 4/1) on growth quality hydroponic cultivated spinach. The results showed that when intensity increased, plant height, leaf number, root length, width, shoot fresh weight, dry weight were increased but specific shoot-to-root ratio did not increase. highest values parameters observed under s-1 treatment, while lowest 90 treatment. At higher intensities, K+, oxalic acid nitrate contents tended decrease Ca2+ content. Meanwhile, Fe2+, crude fiber, soluble-solids, total polyphenol vitamin C treatment organic Our indicated among all experimental lighting treatments, best