Automated Measurement and Control of Germination Paper Water Content

Area of Science:

• Plant Science
• Agricultural Engineering
• Measurement Science

Background:

• Germination paper (GP) is a common plant growth substrate.
• Current methods neglect GP water content and dynamic variations.
• Existing irrigation lacks control over water deficit intensity over time.

Purpose of the Study:

• To develop a novel measurement and control system for precise GP water content regulation.
• To enable studies on plant development under dynamic water deficit conditions.
• To overcome limitations in current plant growth studies using GP.

Main Methods:

• Utilized capacitor discharging to measure GP electrical resistance, correlating it with water content.
• Employed a Kalman filter with an evapotranspiration model and experimental data for measurement refinement.
• Implemented a model predictive controller (MPC) for dynamic irrigation control based on refined measurements.

Main Results:

• Achieved improved measurement accuracy of GP water content to 0.22 g/g.
• Attained an overall control accuracy of 0.09 g/g using MPC for water content regulation.
• Demonstrated the capability to precisely control varying water content in GP.

Conclusions:

• The novel method allows for accurate control of GP water content, enabling dynamic water deficit studies.
• This approach addresses limitations in existing plant growth studies.
• Facilitates research into the relationship between dynamic water deficit and plant development on GP.