Effects of Irradiation with LEDs During Night on Growth and Cut Flower Quality of Gerbera hybrida

Abstract

Gerbera is one of the important floricultural plants in Japan, and year-round production has been established with soilless culture. Here we investigated the effects of night lighting with red and far-red light emitting diodes (LEDs) on the growth and flower quality of cut gerberas. In the one-year-old gerbera ‘Sandy’, the combinations of end-of-day and night break lightings with either red or far-red LEDs significantly increased the scape length and cut flower weight. In addition, all-night lighting with red LEDs also increased them. However, night lighting with far-red significantly reduced SPAD values in leaves. Of the three night-time periods (end-of-day, night break, and end-of-night), night break was the most effective for elongation of the scape length. In addition, night lighting with red LEDs in a long-photoperiod and high-temperature season (from June to August) might decrease the scape length of cut flowers in October. Taken together, night break lighting for around 4 hours with red LEDs might improve the cut flower quality of gerbera.