Abstract
Systemic acquired resistance (SAR) inducers and dioxygenase-inhibitors represent an alternative approach for controlling fire blight. Acibenzolar-S-methyl (ABM), prohexadione-Ca (ProCa) and trinexapac-ethyl (TrixE) were tested in vitro and under field conditions for their efficacy in reducing fire blight incidence and severity. Under field conditions, these compounds significantly reduced (up to 40%) fire blight incidence. Similarly, in vitro, resistance inducers slowed down the pathogen migration in both the xylem and the parenchyma. In particular, the application of ProCa and TrixE resulted in a 50-60% reduction of pathogen migration inside the plant tissues.