Courtesy Agricultural Research ServiceResearcher Dong Wong examines leaves of peach trees that received deficit irrigation treatments.Infrared temperature sensors may help guide peach growers about the optimum times to irrigate their crop.
Research conducted by the Agricultural Research Service involved 12 infrared temperature sensors installed in peach orchards at the ARS San Joaquin Valley Agricultural Sciences Center in Parlier, Calif., according to a news release.
Researchers Dong Wang and Jim Gartung applied one of four irrigation treatments to the trees: furrow or subsurface drip with or without post-harvest water stress.
They measured crop yields and fruit quality, comparing trees grown under deficit irrigation with those grown under normal conditions.
The researchers used the sensors to measure temperatures in the tree canopies and calculated a crop water stress index.
The index was the difference between tree canopy temperatures and ambient air temperatures. The higher the number, the more tree stress.
The researchers found a 10- to 15-degree difference midday in trees undergoing water stress compared to 3 or 4 degrees in trees that were not stressed.
They also used a pressure chamber to measure midday stem water potential, another measure of water stress.
The results correlated with those of the infrared sensors, which means the sensors may be another tool to help manage orchard irrigation.