Effects of short-term hypersalinity exposure on the susceptibility to wasting disease in the subtropical seagrass Thalassia testudinum

► Elevated salinity decreased total chlorophyll and lesion size in infected seagrass. ► Elevated salinity increased H2O2 production in T. testudinum. ► Elevated salinity and infection did not affect seagrass photosynthetic efficiency. ► Labyrinthula colony growth was reduced at 80 μM H2O2.