Abstract
Plant water content (PWC) affects growth, yields and quality of the plants. We have developed a needle-type PWC sensor with humidity sensitive polymer, polyethersulfone (PES) membrane. When the sensor is insert into a plant, PES absorbs water from the plant according to its water content. The electric impedance of PES is determined by the amount of the absorbed water and reflects the PWC. This sensor is based on a glass tube and soaked into PES solution to form a PES film. However, this sensor is fragile for brittleness of the glass and it is difficult to layer a film thickness for pipe-formed structure. In this paper, we propose the plane-formed structure sensor based on an acrylic board. As a result of switching from, we can produce PES film and a base separately. We performed the performance evaluation with an old sensor and performed the fluid volume monitoring of the strawberry.
