Definition
Damping off is death of a seedling before or shortly after emergence due to decomposition of the root and/or lower stem; it is common to distinguish between preemergence damping-off and postemergence damping-off.
Above: Damping off of a young coffee (Coffea arabica) seedling, associated with a Fusarium sp. a fungus). Note the necrosis of teh stem just at and above the soil line.