Leaf spot and melting-out disease is caused by which type of organism?

Leaf spot and melting-out disease is caused by which type of organism?

• A. Fungus
• B. Bacteria
• C. Virus
• D. Nematodes

Answer: (A)

Fungal pathogens are responsible for leaf spot and melting-out disease. Fungi spread through spores and thrive in moist, warm conditions, producing the characteristic leaf spots with defined edges and, in severe cases, tissue collapse that looks like melting out. That’s why fungi are the most likely cause among common plant pathogens. Bacteria can also cause leaf spots, but those lesions are typically water-soaked and may ooze. Viruses often cause mosaics, mottling, or stunting rather than distinct spots. Nematodes mainly target roots and underground parts, not the leaf symptoms described.

Fungal pathogens are responsible for leaf spot and melting-out disease. Fungi spread through spores and thrive in moist, warm conditions, producing the characteristic leaf spots with defined edges and, in severe cases, tissue collapse that looks like melting out. That’s why fungi are the most likely cause among common plant pathogens. Bacteria can also cause leaf spots, but those lesions are typically water-soaked and may ooze. Viruses often cause mosaics, mottling, or stunting rather than distinct spots. Nematodes mainly target roots and underground parts, not the leaf symptoms described.