Bacterial inflorescence rot

Bacterial inflorescence rot (BIR) is a disease of grapevines caused by the bacterium Pseudomonas syringae pv. syringae (PSS). The pathogen is not known to be a risk in a typical warm and dry growing season, but when wet weather prevails in spring and summer it can be responsible for significant yield loss, especially in cool regions with humid conditions. This page provides links to a fact sheet about PSS and BIR to help growers recognise and manage this grapevine disease.