Received: 24-10-2019 / Accepted: 02-04-2020
Basil is widely cultivated in Vietnam and mostly used for spice and medicinal purposes. In this study, in vitrobasil plants were cultivated under three blue LED light conditions (440, 450, and 460nm,respectively)byusing fluorescent lamps asthecontrol. After four weeks, the morphology, biomass, gas exchange in photosynthesis, chlorophyll, total sucrose, starch, phenol compounds and total flavonoid content of the plants were determined. Under the fluorescent light or blue LED of 450nm, the stem height was lower, but the number of leaves was greater, and the total leaf area was higher than those of plants grown under blue LEDs (440 and 460nm). Root dry mass percentage of the plants under blue LEDs decreased compared to that of the control. Blue LED at 440 and 460nmincreased the percentage of stem dry mass, whereas blue LED light (450nm) increased the percentage of leaves dry mass. Monochromatic blue light reduced photosynthetic rate, chlorophyll a, sucrose, starch, and phenol compounds content of leaves. However, blue LED light (450nm) maintained the carotenoid and flavonoid contents, chlorophyll a/b ratio in leaveswhich were rather highin comparison with the fluorescentlightof the control.