Night interruption improves subsequent cut flower quality in Cymbidium ‘Red Fire’

The influence of night interruption (NI) on cut flower quality was examined during subsequent Cymbidium flowering. Forty-two-month old Cymbidium ‘Red Fire’ plants were subjected to first-flower cutting and were regrown for subsequent flowering in the following year. The plants were exposed to 9 hour natural light (control) or 9 hour natural light plus NI from 22:00–02:00 HR with low light intensity (LNI) at 3–7 µmol·m⁻²·s⁻¹ or high light intensity (HNI) at 120 µmol·m⁻²·s⁻¹. NI treatments accelerated subsequent flowering and increased the number of inflorescences, the number of flowers per inflorescence, and the inflorescence length compared with those of control plants. The red coloration of petals increased under both LNI and HNI conditions compared with that of control plants, which was represented by increases in a* and total anthocyanin content. These results indicate that NI lighting enhances the cut flower quality and accelerates the subsequent flowering time of Cymbidium for cut flower production. NI could be an effective method for maintaining long-term productivity of high-quality Cymbidium flowers.