Historically credited as being the first bacterium ever characterized as a plant pathogen, fire blight is a bacterial disease that leads to significant losses of pear and apple. The role of insects in the spread of this disease has been long studied. In a new study, plant pathologists based at Cornell University and Cornell AgriTech take a hypothesis that has been more or less ignored for 100 years and provided support for its validity.
According to first author Matthew Boucher, the study describes a long hypothesized but never experimentally supported transmission mechanism for fire blight. Boucher and colleagues show that flies in an apple orchard can acquire the bacterial agent (Erwinia amylovora) of fire blight from sugary droplets exuding from diseased apple trees and subsequently transmit the bacterium to uninfected shoots so long as those