What causes Fire Blight in plants?

Fire Blight is caused by a specific bacterium known as Erwinia amylovora. This pathogenic bacterium primarily infects members of the Rosaceae family, which includes various fruits and ornamental plants, such as apple, pear, and quince. Fire Blight manifests as a devastating disease characterized by the wilting and blackening of blossoms, young shoots, and branches, giving the appearance of being scorched by fire.

The bacterium spreads through natural openings, such as flower blossoms, and can also be transmitted by insects, water, or human activity. Conditions that promote high humidity and moderate temperatures contribute to the rapid spread of Fire Blight, making it a significant concern for plant health.

Other options discussed—such as insects, fungus, and nematodes—do not cause Fire Blight. While insects can be vectors for the bacterium, they do not directly cause the disease. Fungi and nematodes are associated with other plant diseases and phytopathologies but are unrelated to Fire Blight’s etiology. Understanding the bacterial cause of Fire Blight underscores the importance of implementing appropriate management practices to prevent and control bacterial infections in ornamental and fruit-bearing plants.