Location: Horticultural Crops Research UnitTitle: Application of small unmanned aerial systems for spatial and temporal assessment of plant water deficits and irrigation needs in red raspberry
Submitted to: International Rubus Ribes Symposium
Publication Type: Abstract Only
Publication Acceptance Date: 12/17/2018
Publication Date: 6/26/2019
Citation: Bryla, D.R., Orr, S.T. 2019. Application of small unmanned aerial systems for spatial and temporal assessment of plant water deficits and irrigation needs in red raspberry. Abstract for International Rubus Ribes Symposium XII International Rubus and Ribes Symposium; 2019 June 26-28; Zurich, Switzerland.
Technical Abstract: Many berry growers are facing serious water limitations due to warmer and drier weather conditions, increased regulations, and greater demand by other sectors. The goal of this project is to utilize remote sensing technology to develop practices that will enable a user to quickly assess spatial variability in crop water status and adjust irrigation and water allocations accordingly. Currently, there is very little information on the seasonal water requirements of berry crops, including raspberry (Rubus idaeus L.). Most growers rely on visual assessments of the soil and apply irrigation at a rate of 25-50 mm of water per week. In many cases, the plantings are over watered and susceptible to root rot. We are evaluating new remote sensing techniques for assessing the need for irrigation, including NDVI and thermal infrared imagery in commercial fields of red raspberry in northwest Washington, USA. These images are collected using a low-altitude, unmanned aerial system (UAS or drone) and analyzed to develop robust field-specific estimates of crop development and irrigation water requirements. NDVI images are used to track canopy development and estimate basal crop coefficients throughout each stage of plant development. Temperatures are extracted from the thermal images using an automated-based method for the image segmentation and analyzed to assess spatial variability in water status of the fields. While physiologically-based indicators can only be measured in a limited number of plants, thermal imagery provides information quickly on every plant on the farm. With sufficient resolution, fields can be mapped on a block-by-block basis, providing an invaluable tool for water management and using deficit irrigation strategies. As a result of this research, we will eventually be able to provide raspberry growers with state-of-the-art water management tools for reducing irrigation and energy use, avoiding water limitations, and improving production and fruit quality.