WATER STRESS DETECTION IN A ‘CONFERENCE’ PEAR ORCHARD IN A TEMPERATE CLIMATE USING SAP FLOW MONITORING

Drip irrigation in ‘Conference’ pear trees in Belgium and The Netherlands is used to maximize fruit yield.
Belgium is situated in the temperate climate zone with a relatively low average evapotranspiration and a high but variable rainfall.
Current irrigation scheduling techniques are based on soil water balance models or soil moisture sensors.
Continuous plant based measurements can improve the precision of these irrigation scheduling techniques because they are more connected to metabolic and physiological processes.
However, continuous plant based measurements in field conditions in a temperate climate are scarce.
In this experiment sap flow monitoring was used to detect water stress in a pear tree orchard in Belgium in 2011. Stem (Ψ_stem) and soil water potential (Ψ_soil) were measured in a control irrigation (CI), partial irrigation (PI) and non-irrigation (NI) treatment.
Thermal dissipation probes were used to detect differences in sap flux density (J_p) between the treatments.
Between the PI and the CI treatment no differences in Ψ_stem or J_p were observed.
A lower J_p tendency was observed in the NI treatment.
The detection of J_p differences under low evaporative conditions, applying moderate water stress, opens the door for plant based irrigation scheduling in pear trees in a temperate climate.

IX International Workshop on Sap Flow

P. Janssens, A. Elsen, T. Deckers, J. Vanderborght, J. Diels, H. Vandendriessche

irrigation, thermal dissipation probe, Watermark sensor, stem water potential (Ψ_stem), soil water potential (Ψ_soil)

https://doi.org/10.17660/ActaHortic.2013.991.52