Effect of Light Quality on the Three Selected Microgreen Species Under Ambient Conditions

A study on the use of different (red + blue (RB), white + red (WR), white + blue (WB), and white + red + blue (WRB)) light-emitting diodes (LEDs) on three microgreen species (amaranth, cabbage, and lettuce) was conducted. The study was conducted to evaluate the effect of LEDs on shoot system, root length, and fresh weight of the three microgreen species. Microgreens were grown under ambient conditions (temperature: 28± 2 °C; relative humidity: 65 ± 5%) and arranged in a Completely Randomized Design with four replications. Microgreens were harvested at 14 days after sowing. Results show that hypocotyl and shoot lengths of amaranth were not affected by any of the LEDs. But for cabbage, either RB, WR, or WB was used for longer hypocotyls and shoots, whereas for lettuce, WB was needed to obtain longer hypocotyls, but none of the LEDs produced longer shoots. LEDs such as WRB produced longer roots across microgreen species. None of the LEDs showed an impact on shoot fresh weight across microgreen species.