A team of researchers has discovered important insights regarding how plants endure in frigid environments.
While plants require light for growth, excessive exposure can harm a crucial component of photosynthesis called photosystem II. It’s understood that plants that thrive in bright sunlight are more adept at repairing this light-induced harm. However, their repair processes tend to decline when temperatures fall. An international research team led by Osaka Metropolitan University has now uncovered some fundamental aspects of how plants cope in colder climates.
Associate Professor Riichi Oguchi, along with his colleagues from Australia, Austria, and Japan, cultivated Arabidopsis thaliana (widely known as thale cress) using various ecotypes sourced globally. They began by growing all the plants at 22°C. Afterward, a group was left at this temperature as a control, while the others were exposed to 12°C for three days. This was followed by placing all plants in conditions of 5°C for the experiment.
The reduction in photosynthetic ability caused by light—referred to as photoinhibition—undergoes repair at a particular rate in plants. The control group of Arabidopsis thaliana exhibited no variation in the repair rate between different ecotypes at 5°C. In contrast, the plants that had acclimated to colder temperatures for three days demonstrated an enhanced rate of photoinhibition repair, with those from colder regions showing a greater improvement.
“Our findings indicate that plants which acclimatize in cold environments enhance their ability to repair photoinhibition when in low temperatures. Moreover, ecotypes from colder areas exhibit a greater capacity for such acclimation,” stated Professor Oguchi. “However, evidence from the control group suggests that during warmer months, plants do not boost their repair rates as the energy costs associated with this repair process are significant.”
