Self-adhesive sensors on the leaves of plants will tell when they are “thirsty”
Electronic sensors that will be placed on the leaves of the plants and will alert when the plant wants water have been made by researchers in the US.
Engineers at MIT University, led by Professor Michael Stran of the Department of Chemical Engineering, have published in the “Lab on a Chip” journal of the Royal British Chemistry Society, describing the creation of electronic circuits that can be printed. These sensors are placed on the leaves and “test” when the plants are thirsty for water.
This new technology will not only help in cases of negligence, for example plant owners who do not remember when to water them and when to water them. Most importantly, as the AMP explains, it can help farmers in the future learn early on when to water their crops, especially given the climate change and the growing threat of drought.
“We have created the most timely drought warning tool that has agricultural applications. It is difficult to get such information about plants otherwise. One can put sensors in the soil or use satellite instruments, but he will never really know if a particular plant needs water, ”said Strano.
Researchers have already begun working with a large US agricultural product company to develop sensors for widespread use in crops.
When the soil dries, the plants slow down their growth and reduce their photosynthetic activity, while their tissues are damaged. Some plants give up their problem due to lack of water, but many others do not show visible signs until they have suffered significant damage.
The new sensor utilizes the so-called plant mouths, the small pores on the leaf surface that allow water to evaporate. As this happens, the water pressure inside the plants drops, allowing them to draw water back from the soil. Mouths open the day when exposed to light and close at night.
To create the sensor, MIT researchers used carbon nanotube ink (tiny hollow carbon tubes that are good conductors of electricity) dissolved in an organic substance that does not harm the plants’ mouths. This “ink” can be printed on the sheets to create an electronic circuit, which records when they open and when the mouths are closed.
By monitoring this lock for days in conditions of both humidity and drought, the researchers found that they could detect when the plant needed water. They found that mouths usually take seven minutes to open when there is light and 53 minutes to close when darkness falls. However, when there is a shortage of water, the mouths take an average of 25 minutes to open and 45 minutes to close.
Researchers are already developing an easy way to mount the sensor, a sticker that will be applied to the surface of the leaf.