Growth and flowering characteristics of Calendula under different light spectra in a controlled environment

Healthy food is getting more and more attention.
Edible flowers are enriched in phytochemicals and considered as one of the sources of nutrient foods.
Since farming has benefited from the development of environmental control technologies, high-quality crop production with high efficiency becomes possible.
This research aims to investigate how the growth and flower characteristics of calendula plants respond to different light spectra.
Two calendula cultivars were grown under a controlled environment (plant factory) hydroponically.
At the flower initiation stage, plants were exposed to four different light spectra including white (control), 50% blue (B50), 50% red (R50) and 50% far-red (FR50). Plant growth parameters and flower characteristics were recorded 78 days after sowing, while number of flowers was recorded every two days after transplanting.
The results show that plants grown under FR50 tend to be the highest in plant height, and contrastingly, the chlorophyll content of leaves tends to be the lowest.
The days from flower bud to full bloom were shortened by R50 and FR50, and the total number of flowers and total flower weight per plant were also increased by R50 and FR50, compared with the control or B50. However, there was no significant difference in the characteristics of individual flower under different light spectra.
These results demonstrate that plant growth and flowering of calendula can be regulated by the light spectrum.

IV Asian Horticultural Congress – AHC2023

M. Munyanont, N. Lu, T. Joilek, D.F. Rachma, M. Takagaki

pot marigold, edible flower, LEDs, light quality, artificial lighting

https://doi.org/10.17660/ActaHortic.2024.1404.191