Light and Plants
Light and Plants
We provided information about Light and Retinal Cells last week. This week, we will share a story of Light and Plants with you.
Plants recognize the shades of neighboring plants by sensing the ratio between red and far red light using specific light sensors so called the phytochrome. In the shades formed by the foliage of neighboring plants, the ratio of red over far red light increases because red light is mostly absorbed by chlorophylls whereas far red light is reflected by leaves. When the ratio of red over far red light increases, phytochrome change their structure from Pr to Pfr, which leads to shade avoidance responses including stem elongation via increase of auxin concentrations in plant cells (Fig 2).
In addition, plants sense the seasonal change in light intensity, the length of daytime, temperature, etc. and decide when to germinate, when to grow and when to bloom. Daily and seasonal change in plants are cued by changes in the quality and quantity of sunlight and orchestrated by the biological clock in plants. Perilla plants were reported to produce only 6% of seeds when grown next to street lights. It is because the biological clock of plants was disturbed by the artificial light overnight.
Thank you, Jinwon Kim, Ph.D. Biologist * Next week’s topic : Light and fish. |