A subsurface capillary irrigation system with a water source buried in a soil has been developed for precision irrigation. This system has advantages in the efficient irrigation to save much water and the real time measurement of evapotranspiration of plants. Creating this new subsurface capillary irrigation system requires deep understanding on detail infiltration responses in soil-root system.

This study aims to analyze the water movement in soil root-system based on the experimental concepts of the observation during infiltration responses and the development of adaptive control for the infiltration process. The experimental analysis was carried out as a function of gravity potentials from the level of a reservoir which was connected directly to the water source under the various climate conditions in a growth chamber. The advance of wetting front formed around the water source was captured by using a time lapse camera. The dynamic water content and its rate in the soil-root system were monitored at different plant growing stages. The Infiltration responses were characterized by the time constant of the infiltration process after giving a step input of the gravity potentials. All these data will be used to create a new precision irrigation control method to adaptive various environmental changes.