1a.Objectives (from AD-416):
Determine the feasibility of measuring grapevine water use during deficit irrigation using capacitance probes monitored remotely.
1b.Approach (from AD-416):
Capacitance probes used to monitor soil water content will be installed on three treatments at 4 locations that are part of the NIFA-SCRI research project to evaluate yield response to deficit irrigation. Data will be collected using a cellular phone and internet protocol. Data will be downloaded and processed daily and compared to the irrigation treatments to evaluate the system.
This project contributes to meeting objective 2 “Develop sustainable water management strategies for perennial horticultural crops with limited and impaired water supplies” of the parent project. Effective water management requires accurate measurement of soil water. This agreement provides access to automated soil water measurement equipment that provides the data needed to meet the objectives of the search. Soil probes were installed by PureSense in each of the 4 water management research sites located in Paso Robles, Delano, Caruthers and Mecca, California. The probes are being used to monitor the changes in soil water content on 2 table grape sites, a raisin crop, and on wine grapes. The sites range from 80 to 500 km from the Water Management offices in Parlier, California. The distance from the office to the field sites makes routine monitoring of soil water content impossible. This system provides real time data on the soil water content at each site to a depth of 1.5 m in 30 cm intervals. It also provides climate data above and below the canopy at each location as well as runtime for each irrigation. The ability to compare plant response with applied water is critical for characterizing the effect of deficit irrigation on yield and plant growth and this equipment facilitates those comparisons. Soil water data are needed if growers want to manage irrigation in real time in response to limited availability of water. The first year of operation has demonstrated the ability of this technology to operate successfully over long distances. We will be using the soil water data along with plant temperature data to characterize the effect of deficit irrigation on early season grapes harvested in the Coachella Valley of California. The soil water data are essential in interpreting the effects of the water management strategies on yield response as well as the potential for deep percolation losses. A smart phone app enables the user to check on system when they are away from a computer. The system is very robust and has worked well since installation.