Some of us have been blessed with a green thumb while others have difficulty with their plants lasting the week.  To be fair to so-called “black-thumbed” readers, it’s not exactly easy to tell what the cause of a plant’s ailment is; for crying out loud, who knew cacti could get sunburns?  

Strawberries are one of the plants monitored in this study. Picture courtesy of Creative Commons.

Fortunately, a publication in April 2020 from MIT may be the answer to all plant parents’ prayers.  A team of engineers has developed a way to track how plants respond to a variety of everyday stresses.

According to the head of the study, Michael S. Strano, plants use bursts of the chemical hydrogen peroxide to signal that it has been injured.  The distress beacon stimulates nearby leaf cells that then produce the necessary materials to aid in the healing process.  This can be seen when you pluck off a leaf: within the span of a few days, a callous has formed to protect the plant from potential infection.

Understanding plants’ response to stress can act as a preventative measure to crop failure.

Strano’s lab has been able to monitor these stress releases via carbon-based nanotubes, extremely small sensors that are embedded in the sample plant’s leaves.  The waves of hydrogen peroxide are detected by the nanotubes, and through graphical analysis, the engineers are able to distinguish between different types of stress and different species of plants. 

They hypothesize that each plant responds differently to stress because every plant has different mechanisms to counteract the damage.  For example, while a cactus is able to be burned by the sun, it has a much higher capability of dealing with sunburn as opposed to being cut in half.  This particular study utilized strawberries, arugula, spinach, and other common crops (all of which produced different signals),  but in theory, the nanocarbon tube sensors should be applicable to any type of plant.

Picture courtesy of Creative Commons.

This leads the research team to believe their work could be beneficial to the field of agriculture.  By being able to identify what stressors impact plant growth the most, farmers can adjust their fields and greenhouses to better accommodate their crops.  This, in turn, will produce a higher yield of food.

As of right now, Strano’s lab is able to accurately analyze plants’ stress in response to physical injury, infection, heat, and light damage.  In the future, they hope to use this information and method to determine why some plants are immune to certain pathogens and others are not.

Tedrick Thomas Salim Lew, Volodymyr B. Koman, Kevin S. Silmore, et. al. Real-time detection of wound-induced H2O2 signalling waves in plants with optical nanosensors. Nature Plants, 2020; 6 (4): 404 DOI: 10.1038/s41477-020-0632-4