EVALUATION OF PLANT AND SOIL MOISTURE SENSORS FOR THE DETECTION OF DROUGHT STRESS IN RASPBERRY

A preliminary experiment evaluated seven different methods of monitoring and predicting drought stress in ‘Heritage’ red raspberry plant (Rubus idaeus L.). Four leaf methods included: leaf water potential (PMS 600 pressure bomb), leaf photosynthesis (Li Cor, LI 6200 portable leaf photosynthesis system), chlorophyll fluorescence (Hansatech FMS 2) and leaf stomatal conductance and transpiration (LI 1600 porometer). The four other methods monitored plant stress indirectly by monitoring soil moisture status or remote sensing principles.
The soil moisture methods included: tensiometer, gravimetric (weighing) and volumetric (HydroSense®) while the remote sensing method used a spectroradiometer (GER 3700). The best instruments to detect early signs of drought stress in the plant included the pressure bomb, leaf porometer and leaf photosynthesis of which the last two are non destructive.
Measurements within the soil that were closely associated to plant stress included the gravimetric method and the HydroSense.
Of these, the HydroSense was the most versatile.
The limitations of the tensiometer in very dry soils render it impractical for drought studies.

XXVI International Horticultural Congress: Environmental Stress and Horticulture Crops

J.-P. Privé, D. Janes

pressure bomb, photosynthesis, stomatal conductance, fluorescence

https://doi.org/10.17660/ActaHortic.2003.618.46