Protocol for diagnosing Erwinia amylovora infection using a fluorescent probe

Current fire blight diagnosis techniques are DNA based and require specialized equipment and expertise, or they are less sensitive. Here, we present a protocol for diagnosing fire blight using the fluorescent probe, B-1. We describe steps for Erwinia amylovora culture, implementing a fire blight-infected model, and E. amylovora visualization. This protocol allows for detection of fire blight bacteria of up to 10² CFU/mL on plants or objects in just 10 s with a simple application including spraying and swabbing. For complete details on the use and execution of this protocol, please refer to Jung et al.¹.