Plants harness sunlight to power photosynthesis, yet excessive light can damage their vital mechanisms and stunt their growth. While adequate light is crucial for plant development, too much can harm photosystem II, a key component of the photosynthetic process.
It is known that plants adapted to growing under full sun repair this light-induced damage more. However, their repair abilities falter in colder temperatures, posing a challenge for survival in cooler regions.
An international research team led by Associate Professor Riichi Oguchi from Osaka Metropolitan University has made significant strides in understanding how plants endure colder environments. By studying Arabidopsis thaliana, or thale cress, from diverse ecotypes around the world, the team initially grew these plants at a stable temperature of 22°C. Some remained as a control group, while others faced a chill of 12°C for three days.
After this exposure, all plants were subjected to the even colder conditions of 5°C. This research could hold the key to unlocking plant resilience in the face of climate challenges.
Photoinhibition, the damage to photosynthesis caused by light, has a repair rate in plants that is crucial for their resilience. In a study of Arabidopsis thaliana, the control plants showed no significant variation in repair rates across different ecotypes at 5°C. However, after just three days of acclimation to cold conditions, these plants demonstrated a remarkable increase in the rate of photoinhibition repair.
The ecotypes originating from colder climates exhibited an even greater capacity for this repair, showcasing their enhanced adaptability.
“What we found in this experiment is that plants acclimated in cold temperatures increase their rate of photoinhibition repair in the cold, and the acclimation capacity is higher in the ecotypes from colder regions,” explained Professor Oguchi. “But during the warmer seasons, as suggested by the control group, the plants do not increase the rate as the cost of such repair capacity is high.”
Journal reference:
- Riichi Oguchi, Soichiro Nagano, Ana Pfleger, Hiroshi Ozaki, Kouki Hikosaka, Barry Osmond, Wah Soon Chow. An Intraspecific Negative Correlation Between the Repair Capacity of Photoinhibition of Cold Acclimated Plants and the Habitat Temperature. Plant, Cell and Environment, 2024; DOI: 10.1111/pce.15270
