Within the FruitCREWS COST Action, Working Group 2 (WG2) focuses on selecting and harmonising physiological and geospatial models that can improve irrigation management in fruit orchards. The group works on integrating advanced modelling approaches that help predict orchard water needs across different environments. By assessing existing process-based platforms such as Qualitree and Olivecan, WG2 contributes to the development of accurate and interoperable tools that support better irrigation decisions worldwide.
Over the first three years of the Action, WG2 has advanced several innovative crop-water modelling approaches aimed at improving resource allocation in fruit production systems. One notable contribution was led by Sergio Velez, who developed a modelling framework that integrates the FAO-56 crop-water demand model with canopy cover information derived from UAV imagery. This approach allows researchers and practitioners to diagnose hydraulic oversizing in drip irrigation systems.
The research introduced a new indicator called the Relative Oversized Ratio (ROR), designed to evaluate the degree to which irrigation systems may be oversized. In addition, the team developed a simplified “irrigation ecolabel” concept that helps assess irrigation performance. To support transparency and reproducibility, the entire analytical workflow has been released as open-source software, enabling researchers and practitioners to benchmark irrigation systems and compare results across different environments.
Another important contribution was made by Or Sperling and collaborators, who developed the Geographic Water Budget (GWaB) approach specifically for almond orchards grown in arid environments. This model uses a water-yield productivity function to identify optimal production conditions, showing that reproductive gains can increase up to 1,350 mm of seasonal transpiration. The model also improves prediction accuracy by incorporating rainfall contributions and site-specific soil water holding capacities, making it particularly relevant for water-limited regions.
Looking ahead to the final year of the Action, WG2 plans to expand its work by conducting a comprehensive survey of applied case studies involving both internal and external crop-water models. The group aims to define a standardized set of performance parameters that will allow systematic benchmarking of these models across diverse agricultural systems. This evaluation will help ensure that the selected modelling tools are not only scientifically robust but also scalable and practical for real-world orchard management.
Reflecting on the group’s progress, Prof. Kathy Steppe, leader of WG2, highlighted both the scientific achievements and the importance of capacity building:
“I am proud of the significant strides our Working Group has made over the past three years. In addition to our fundamental work on complex plant-water models and the integration of sensor data with mechanistic plant models for improved irrigation scheduling in fruit trees, we have made the training and empowerment of the next generation of researchers a central priority. Through a targeted COST training school and the STSM tool, we have equipped early-career scientists with the technical skills required to develop and advance the next wave of predictive models, ensuring continued innovation and long-term sustainability in fruit-tree water management.”
Through its work on crop-water modelling, WG2 contributes directly to the FruitCREWS mission of improving irrigation strategies under increasing water scarcity. By developing robust modelling tools and supporting knowledge exchange across the network, the group helps ensure that fruit production systems remain productive and sustainable even under changing climate conditions.
Working Group Leader:
Prof. Kathy Steppe
Ghent University
Kathy.Steppe@UGent.be