Fire blight research: 2026 and beyond
TL;DR
Advances in fire blight research are highlighted including topics such as host-pathogen interactions, particularly work on the type III secretion system and biofilm formation, and the linkage of horticultural management with fire blight management.
Abstract
Fire blight disease, caused by the highly virulent bacterial pathogen Erwinia amylovora , is a devastating disease that continues to spread to new regions worldwide. High-density planting systems for apple combined with large plantings of consumer-preferred but highly susceptible cultivars have fueled disease outbreaks that can result in significant numbers of tree losses. These cultivation trends, together with the aggressive nature of the pathogen, make fire blight management extremely challenging. The fire blight research community recently met at the Fourth International Symposium on Fire Blight of Rosaceous Plants in Richland, Washington USA in June, 2025. This meeting offered an opportunity for interaction among scientists with expertise in plant pathology, microbial genetics, horticulture, and plant breeding and genetics. Here, we discuss key ideas arising from discussions at the meeting and highlight advances in fire blight research including topics such as host-pathogen interactions, particularly work on the type III secretion system and biofilm formation, E. amylovora infection biology, host resistance and breeding strategies for fire blight resistance in apple and pear, fire blight disease management from global to farm scale, biocontrols, and the linkage of horticultural management with fire blight management. Finally, we provide guidance for future research as we look for both incremental and transformational gains in understanding the E. amylovora -fire blight pathosystem that can lead to significant advances moving towards successful, sustainable disease management.