Grapevine drought tolerant ideotypes to adapt viticulture to climate change

Abstract

Context and purpose of the study. Climate change is challenging the resilience of grapevine, one of the most important crops worldwide. Adapting viticulture to a hotter and drier future will require a multifaceted approach that must include new management strategies, increased irrigation efficiency, and the identification of more drought tolerant genotypes. In this study we used a multi-trait phenotyping approach and model-assisted analyses to identify grapevine drought tolerant ideotypes.

Material and methods. We quantified a broad range of hydraulic traits under drought across and within Vitis species (5 different species and 5 different cultivars of V. vinifera). We then created in silico libraries of new trait combinations by varying and rearranging these quantified traits at random. Finally, by modelling the performance of existing cultivars, along with these novel trait combinations, we identified elite grapevine ideotypes with increased drought tolerance and superior performance under future climate change scenarios.

Results. The results of our study demonstrated that elite ideotypes have the potential to outperform existing varieties across important wine regions and under future climate scenarios. Overall, elite genotypes exhibited traits that reduce plant transpiration such as leaf area and minimum conductance, an increased net photosynthesis and hydraulic safety margins, and a longer time to reach hydraulic failure. This study reveals the traits and trait combinations that can be leveraged to guide breeding programs aimed at increasing grapevine drought tolerance.