Susceptibility of grape berries to stressors such as drought or heat changes according to the stress intensity and duration, but also depending on the berry developmental status at stress occurrence. For example, grapes in the herbaceous phase are more susceptible to drought stress than berries in the ripening stage. Drought and heat stress, which are predicted to increase in frequency and magnitude due to climate change, share a common effect in increasing the production of cytotoxic reactive oxygen species (ROS) in plant cells. The project will explore the different strategies that grape berries could adopt to counteract an increase in ROS molecules produced in response to stressors, including the boost of the antioxidant pool (or de novo biosynthesis of antioxidant molecules) and the modification in the expression of ROS scavenging enzymes.