Erwinia amylovora

Erwinia amylovora is a bacterium that causes the plant disease known as fire blight. This disease primarily affects plants in the rose family, including economically important crops like pears and apples, as well as many ornamental plants.12

Symptoms of fire blight include the sudden browning and death of blossoms, leaves, twigs, and branches, giving the plant a scorched appearance. Cankers can form on branches and trunks, leading to dieback, and fruits may shrivel. The bacteria spread through insects, wind, and rain, and can overwinter in cankers to re-infect plants the following spring. Controlling fire blight is challenging, often involving the removal of infected wood and, in some cases, the use of sprays like streptomycin, though antibiotic resistance is a concern.13