Irrigation automation based on soil electrical conductivity and leaf temperature

Two automated drip irrigation systems: one based on soil electrical conductivity and the other based on leaf–air temperature differential were developed and tested for Okra (Abelmoschus esculentus). Different sensors were evaluated for monitoring the soil moisture content based on electrical resistance variation with moisture content. The sensor with washed sand as porous medium was found to be the most efficient one for the study area. A low cost, commercially available button type thermistor was used as the leaf and air temperature sensors. The amount of water applied per day, leaf–air temperature and soil moisture content were monitored during the study period. The systems maintained the designed soil moisture content and air–leaf temperature differential through out the study period.