Plants are constantly exposed to a wide range of microbial pathogens, many of which can cause disease when environmental conditions favor infection. As climate change increases the frequency and intensity of drought, these conditions may shift in ways that alter how pathogens infect and evolve. This project explores how drought changes the genetic requirements for bacterial pathogens to colonize plant hosts, using the Arabidopsis thaliana–Pseudomonas syringae system as a model. Candidate genes important for pathogen success under drought have been identified through a genome-wide mutant screen, and researchers will help validate these candidates by confirming gene disruptions and testing mutant performance against the wild type. Students will gain experience with core microbiology and genetics techniques, as well as introductory data analysis. Participants will develop skills in experimental design and data interpretation while investigating how environmental stress shapes the evolution of plant pathogens.