- Worldwide distribution. On seeds, bulbs, tubers, fruits and flowers of coconuts, maize, onion, peanuts, rice, and sorghum, and many other hosts. A cosmetic problem.
- A fungus, usually on organic matter in soil, attacks stored fruits, seeds, roots/tubers, if they are wounded. On onions, it infects dying leaves in the field after harvest; from there the bulbs become infected, often along the veins. It also infects onions when “topped” before storage, especially in hot, wet weather.
- Spread occurs as spores in the wind. The fungus is seed borne.
- Cultural control: well-drained land; ensure seed is clean, or treat in hot water (60°C for 15 min.); dry bulbs after harvest, before storage; varietal resistance (those with red scale leaves); collect trash and burn after harvest.
- Chemical control: seed treatment: mancozeb or thiram.
