One of the core objectives of Agriculture 4.0 is the optimization of water use. Today, agriculture accounts for approximately 70% of global freshwater consumption, making water efficiency one of the most critical challenges for the sector.
Our work focuses on the development and application of an innovative plant-based biosensor — an Organic Electrochemical Transistor (OECT) — designed to be inserted directly into the stem of the plant.
This sensor enables continuous, real-time monitoring of variations in the ionic composition of plant sap, providing direct insight into the physiological state of the plant.
The sensor, called BIORISTOR, consists of a transistor channel and a secondary electrode. When an appropriate electrical potential is applied, an electric field is generated that drives ions present in the sap into the conductive polymer deposited on the main channel.
This mechanism allows the BIORISTOR to detect subtle and early physiological changes inside the plant.
The BIORISTOR has been extensively tested under controlled conditions on a wide range of species, including tomato, kiwi, soybean, grapevine, wheat, and river reed.
In tomato plants, the system is capable of detecting the onset of water stress within the first 30 hours, well before visible symptoms appear.
In field applications, the BIORISTOR is connected to an IoT control unit that transmits data to a dedicated application.
The system detects the early onset of water stress and can alert the farmer or farm management systems when irrigation is needed, enabling timely, targeted interventions. This approach significantly reduces water waste while improving crop performance and sustainability.