Plant sensors could provide farmers with an early warning system

Researchers from MIT and the Singapore-MIT Alliance for Research and Technology (SMART) have found signals that indicate when plans are under stress from things like heat, light, or insect or bacterial attack. These signals are produced by a pair of carbon nanotube sensors.

The sensors identify salicylic acid, a chemical that resembles aspirin, and hydrogen peroxide, two signaling chemicals that plants employ to coordinate their stress reaction. As a potential early warning system, the researchers discovered that plants release these chemicals at separate times for each form of stress.

According to the researchers besides pesticides in Dubai, farmers may utilize these sensors to keep an eye out for possible risks to their crops and take action before the harvests are destroyed.

It has been discovered that the user may precisely determine the type of pressure the plant is experiencing when these two sensors are used in tandem. One of the senior authors of the work, Michael Strano, is the Carbon P. Dubbs Professor of Chemical Engineering at MIT. “Inside the plant, you get chemical alterations that fluctuate throughout the day, and each one serves as a fingerprint of a different stress.” Additionally, Strano co-leads the SMART research group’s Disruptive and Sustainable Technologies for Agricultural Precision as a principal investigator.

The paper, published in Nature Communications, has Sarojam Rajani, a senior principal researcher at the Temasek Life Sciences Laboratory in Singapore, as a senior author. Mervin Chun-Yi Ang, associate scientific director at SMART, and Jolly Madathiparambil Saju, research officer at Temasek Life Sciences Laboratory, are the principal authors of the work.

Feeling pressured

Diverse stresses cause diverse reactions in Indoor and outdoor garden plants. The plant cells that use hydrogen peroxide as a signal of distress in response to insect attacks or other stressors like bacterial infections or excessive light exposure were the subject of a 2020 sensor built by Strano’s lab.

These sensors are made of small, polymer-wrapped carbon nanotubes. The sensors may be made to detect different compounds by modifying the three-dimensional shape of the polymers; when the target is present, the sensors will emit a fluorescence signal.

Using this method, the scientists created a sensor for the new study that can identify salicylic acid, a chemical that controls numerous aspects of plant development, growth, and stress response.

The Nano sensors are dissolved in a solution and applied to the base of a plant leaf by the researchers to embed them in the plants. The mesophyll, which is the layer in which most photosynthesis occurs, is where the sensors can live after entering leaves through pores known as stomata. With an infrared camera, it is simple to identify the signal when a sensor is engaged.

The study involved the application of peroxide of hydrogen and salicylic acid sensors to Chinese cabbage, or pak choi, a green, leafy vegetable that is also referred to as bok choy or bok choy. The plants then experienced four separate types of stress: heat, intense light, insect bites, and bacterial infection. It was discovered that each type of stress caused the plants to respond differently.

The plants produced hydrogen peroxide in response to every kind of stress in a matter of minutes, reached their peak production within an hour, and then went back to normal. Different time points within two hours after the stimulus elicited the synthesis of salicylic acid due to light, heat, and bacterial infection. Bites from insects did not increase the synthesis of salicylic acid.

According to Strano, the results show a “language” that vegetation employs to coordinate its stress reaction. Waves of salicylic acid and hydrogen peroxide set off other reactions in plants, enabling them to withstand any kind of stress.

Early Alert

The only method that works with almost any plant is this one, which is the first to get data gathered from a plant in real time. The majority of current sensors are made of fluorescent proteins, which are not widely applicable and need to be genetically altered into a particular kind of plant, such as tobacco or the widely used experimental plant Arabidopsis thaliana.

Currently, scientists are modifying these sensors to develop sentinel plants that might be watched and used to alert farmers much sooner when their crops are experiencing stress. For example, plants in garden pots in Dubai gradually start to turn brown when they don’t get enough water, but by then, it’s typically too late to do anything about it.