Design and development of an auto irrigation system

In scientific irrigation scheduling water should be applied to a crop at an appropriate soil water tension to fulfil its evapotranspiration requirement. Automatic control of water application at predecided soil water tensions is an effective irrigation scheduling technique. This can be achieved through an indigenously developed auto irrigation system. In this system soil water tension is sensed through a modified manometer type tensiometer. The design provides control of irrigation at the predecided soil water tensions and preprogrammed timer. The circuitry can be operated with a 12 V d.c. storage battery for a long period.