British and Australian scientists reported in the prestigious scientific
journal, Nature Plant, in January
2018 that modified plant circadian rhythm can lead to groundbreaking increase
in plant yield. Lighting for 22 hours a day on some specific wheat variety
enabled production of 6 generations per year (Figure 1).
1. Dr. Brande Wulff at John Innes Institute in the United Kingdom led research
of speed-breeding of wheat by modification of circadian rhythm (Photo Credit:
Continuous lighting for 24 hours a day, however, damages plants causing
physiological abnormalities such as chlorosis. Especially, plants under street
lights were found to reduce visits of nocturnal insect pollinators by more than
60% (Figure 2; ref. Vol 21 – Effect of Artificial Lighting on
and even worse, Perilla plants may
barely produce seeds. Turning off lights is as important as lighting for
Figure 2. In the experiments in the Bernese Prealps
with cabbage thistles, continuous artificial lighting at night reduced visit of
nocturnal insect pollinators by 60% and seed production by 15% (Knop et al., Nature, 2017; Photo Credit : University of Bern).
Light Pollution Policy came into effect in France on last
January 1st. It aims to attenuate the level of disturbance to humans,
flora, fauna and ecosystem and to aid enjoying the night sky. It is the first
meaningful movement of mankind to reduce light pollution by and detrimental
effects of artificial lighting.
Jinwon Kim, Ph.D.
* Next week’s topic : Light therapy awarded a nobel prize