What type of organism causes fire blight ?

• A. Bacterial
• B. Virus
• C. Insect
• D. Fungus

Answer: (A)

Fire blight is caused by a bacterium. The pathogen Erwinia amylovora infects apple and pear trees, thriving in warm, wet conditions and spreading through blossoms, wounds, and cankers. This bacterial nature explains the characteristic scorched, wilted tissue and ooze you see on affected shoots. It’s not a virus, fungus, or insect—viruses require living cells and usually produce different systemic symptoms, fungi form structures like spores or hyphae, and insects are pests rather than disease-causing organisms. Understanding that fire blight is bacterial helps explain its modes of spread and the kinds of management approaches used.