Pure Photosynthates Extraction Sensor Device with Highly-Precise Phloem/Xylem Position Identification

We propose a pure photosynthates extraction sensor device integrated with highly precise phloem/xylem position identification to quantitatively monitor the components of internal higher plants, which is a key indicator for controlling stable crop production. The essential functions of the device are high-precisely identifying phloem/xylem positions based on electrical conductivity and extracting pure phloem sap. We fabricated the proposed device with microelectromechanical systems technology and evaluated its effectiveness. It is confirmed that the performance of our fabricated electrical conductivity sensor is almost equal to that of a commercially available meter. (The error of these characteristic lines is less than 5%.) Experiments with cucumber stems confirmed that the device can precisely measure the electrical conductivity of phloem/xylem sap in the appropriate range of internal plants or soil (0.0-1.0 mS/cm), identifying their positions stably over a long period. Extraction experiments demonstrated that phloem sap from the internal plant flows readily into the extraction flow channel and a reservoir. Therefore, we clearly demonstrated the feasibility of a novel sensor device that can conveniently identify the phloem positions and extract pure photosynthates samples in agricultural situations.