Two peptides regulate plant leaf aging

Study brings insights into the control of leaf senescence in plants. The research revealed that two small molecules produced by the plant Arabidopsis thaliana have opposite effects on leaf aging. While the SCOOP10 peptide accelerates aging, SCOOP12 suppresses it. These findings may offer new solutions to delay unwanted aging in crop plants.

Senescence is the natural process in which plant leaves break down their internal components and turn yellow. This phenomenon is fundamental to the plant's life cycle, as it allows the recycling of nutrients for the production of seeds and fruits.

However, premature aging, triggered by environmental stresses, is a growing challenge in agriculture. Factors that accelerate senescence include drought, high temperatures and high soil salinity. These conditions are increasingly common due to climate change.

Nora Gigli-Bisceglia, one of the study's authors and a biologist at Utrecht University, explains that senescence is used by plants as an escape mechanism to recycle nutrients under stress conditions.

However, prolonged exposure to stress leads to excessive senescence and eventually plant death. Therefore, understanding the mechanisms of senescence regulation is essential to improve crop management under adverse conditions.

Process regulation

Scientists have discovered that the MIK2 receptor, a protein present on the surface of plant cells, plays a crucial role in regulating this process.

By applying different peptides of the SCOOP family on detached sheets of Arabidopsis, they observed that the SCOOP10 peptide accelerated leaf yellowing, while SCOOP12 slowed the process. This dynamic suggests that the peptides compete for the MIK2 receptor, resulting in opposite responses.

The research also showed that plants unable to produce SCOOP10 exhibited delayed aging, remaining green for up to 40 days, while plants without SCOOP12 aged more quickly. Gigli-Bisceglia highlights that this competition between the peptides may be a mechanism to ensure that leaf aging occurs in a controlled manner, preventing it from occurring too quickly and compromising the health of the plant.

Application in agriculture

In terms of agricultural applications, the scientists suggest that it would theoretically be possible to spray the SCOOP12 peptide on fields to slow down plant aging. This solution could be particularly useful for plants in the Brassicaceae family, such as cabbage, kale and cauliflower.

However, the practice of spraying peptides is not yet common in agriculture due to the high cost of these molecules. Gigli-Bisceglia believes that, with the popularization of this type of treatment, costs could decrease, making it a viable alternative to improve agricultural productivity in a more sustainable way.

More information can be found at doi.org/10.1016/j.molp.2024.10.010