For plants, sunlight means life, but sunlight itself can be a double-edged sword for these life forms. Even if they need light to perform photosynthesis, too much sunlight or even too strong an intensity can irreparably damage the leaves and thus the plant.
This is precisely why plants have developed a strategy to defend themselves against too much sunlight: to dissipate this light as heat.
A new study, conducted by Gabriela Schlau-Cohen, Professor of Chemistry at MIT, and her colleagues in collaboration with other Italian institutes, shows how this delicate process takes place.
Through very sensitive spectroscopic analyses, researchers have discovered that the excess energy they receive from the Sun’s rays is transferred through chlorophyll to other pigments called carotenoids.
In this way, it is possible to release the energy acquired through the Sun in the form of heat to the outside world and this prevents damage induced to the plant’s cells by light.
“This is the first direct observation of the transfer of energy from chlorophyll to carotenoid in the light-gathering complex of green plants,” says Schlau-Cohen. “This is the simplest proposal, but no one had been able to find this photophysical pathway until now.”
The researchers also found that environmental conditions can influence the rate of energy dissipation.
This study and a further improved understanding of the natural “photoprotection” system of plants could help in the study of new methods to further maximize yields so that, as Schlau-Cohen herself says, the same crops could be increased by 15-20%.