Like humans take aspirin to treat a stress-induced splitting headache, plants have their own natural remedy for stress. Known as salicylic acid, plants naturally create this chemical substance when exposed to heat and drought. A recent study shows how this process could protect crops from climate change’s effects.
Although salicylic acid is a precursor to aspirin and exists naturally in plants, it has been used for pain relief long before the synthetic medication made its way onto drugstore shelves. For example, ancient Egyptians would peel the bark and leaves off willow trees to soothe their hurting joints. The Greek physician Hippocrates also noted the substance’s pain-relieving and fever-reducing properties.
This new study aimed to better understand the processes involved in producing salicylic acid in plants and the environmental factors that influence this process. They discovered that all living things make reactive oxygen species (ROS), a class of molecules, in reaction to environmental stress.
As an illustration, consider the high quantities of ROS that are produced by human skin in reaction to strong sunlight, which cause freckles and sunburn. However, ROS has a crucial role at lower, safer levels. “At non-lethal levels, ROS are like an emergency call to action, enabling the production of protective hormones such as salicylic acid. ROS are a double-edged sword,” explained Jin-Zheng Wang, the study author from the University of California, Riverside.
Scientists conducted tests on a model plant called Arabidopsis and discovered that heat, persistent sunlight, and drought circumstances drove plant cells to release an alarm chemical known as MEcPP. As this molecule accumulates, it causes the production of salicylic acid, which later plays a significant role in protecting chloroplasts, the organelles responsible for photosynthesis. “It’s like plants use a painkiller for aches and pains, just like we do,” added author Wilhelmina van de Ven.
It is hoped that plants will be better able to withstand climatic change by using this understanding of salicylic acid formation. The result could be more vital crops that can survive greater temperatures, but there may also be numerous other environmental benefits.
Katayoon Dehesh, the senior author of the paper, said:
“Because salicylic acid helps plants withstand stresses becoming more prevalent with climate change, being able to increase plants’ ability to produce it represents a step forward in challenging the impacts of climate change on everyday life. Those impacts go beyond our food. Plants clean our air by sequestering carbon dioxide, offering us shade, and providing habitats for numerous animals. The benefits of boosting their survival are exponential.”
The findings were published in Science Advances on June 3, 2022.