Irrigation of grape and pomegranate by using soil sensors in Apulia Region, Italy

Soil and plant water status can be monitored through different devices, each having advantages and drawbacks. Some plant/soil sensors, such as soil matric potential sensors, can play a key role in scheduling irrigation in orchards and vineyards managed by a more water-efficient use. Soil matric potential (Ψ_m) is an indicator that can be used for irrigation since it can be easily automated with on-time data acquisition. The midday stem water potential (Ψ_stem) is considered a very reliable and accurate indicator of plant water status, but it cannot be automated. The Ψ_m values, automatically collected with data loggers and transmitted through Internet connection on mobile phones/laptops, allowed to keep a good water status for both wine grape and pomegranate. The mean Ψ_m values at 25 and 50 cm depth showed a good correlation with Ψ_stem, indicating that midday stem water potential could be estimated by using Ψ_m values, thus saving time and labor. Since the Ψ_stem is a reliable indicator of the plant water condition, with Ψ_m soil sensors, we could either manage irrigation or estimate Ψ_stem values in a much easier and faster way than using the Scholander chamber (or the pump-up chamber).