Phage depletion of phyllosphere microbiome

Many infectious diseases are associated with altered communities of bacteriophage viruses (phages). As parasites of bacteria, phages can regulate microbiome diversity and composition and may therefore affect disease susceptibility. Yet observational studies alone do not allow us to determine whether altered phage profiles are a contributor to disease risk, a response to infection, or simply an indicator of dysbiosis. We used size-selective filtration to separate plant-associated microbial communities from their respective phages, then transplanted them together or separately onto tomato plants that we subsequently challenged with the bacterial pathogen Pseudomonas syringae.