Photoperiod (Photoperiod): The natural or artificial cycle in which the day and night faced by organisms alternate. Note: The photoperiod is a daily cycle, that is, 24h.
Light period: The period of light in the day-night light-dark cycle.
Dark period: The period of darkness in the light-dark cycle of day and night.
The light morphogenesis effect is regulated by applying a spectrum with a specific mix of 660nm and 730nm. Controlling the flowering cycle, without relying only on the influence of the season, is of great value for ornamental flowers.
The conversion of the phytochrome Pr to Pfr is mainly induced by the deep red light of 660nm (representing the sunlight during the day), while the conversion of Pfr to Pr usually occurs naturally at night, and it can also be excited by 730nm far-red light, as shown in the figure Shown. It is generally believed that the control of plant flowering by phytochrome mainly depends on the ratio of Pfr/Pr. Therefore, we can control the value of Pfr/Pr through 730 nm far-red light irradiation to more precisely control the flowering cycle.
